At 2:28 pm on August 28, 2003, a middle-aged pizza deliveryman named Brian Wells walked into a PNC Bank in Erie, Pennsylvania. He had a short cane in his right hand and a strange bulge under the collar of his T-shirt. Wells, 46 and balding, passed the teller a note. "Gather employees with access codes to vault and work fast to fill bag with $250,000," it said. "You have only 15 minutes." Then he lifted his shirt to reveal a heavy, boxlike device dangling from his neck. According to the note, it was a bomb. The teller, who told Wells there was no way to get into the vault at that time, filled a bag with cash—$8,702—and handed it over. Wells walked out, sucking on a Dum Dum lollipop he grabbed from the counter, hopped into his car, and drove off. He didn't get far. Some 15 minutes later, state troopers spotted Wells standing outside his Geo Metro in a nearby parking lot, surrounded him, and tossed him to the pavement, cuffing his hands behind his back.

Wells told the troopers that while out on a delivery he had been accosted by a group of black men who chained the bomb around his neck at gunpoint and forced him to rob the bank. "It's gonna go off!" he told them in desperation. "I'm not lying." The officers called the bomb squad and took positions behind their cars, guns drawn. TV camera crews arrived and began filming. For 25 minutes Wells remained seated on the pavement, his legs curled beneath him.

"Did you call my boss?" Wells asked a trooper at one point, apparently concerned that his employer would think he was shirking his duties. Suddenly, the device started to emit an accelerating beeping noise. Wells fidgeted. It looked like he was trying to scoot backward, to somehow escape the bomb strapped to his neck. Beep... Beep... Beep. Boom! The device detonated, blasting him violently onto his back and ripping a 5-inch gash in his chest. The pizza deliveryman took a few last gasps and died on the pavement. It was 3:18 pm. The bomb squad arrived three minutes later.

The police began sorting through a trove of physical evidence. In Wells' car, they discovered the 2-foot-long cane, which turned out to be an ingeniously crafted homemade gun. The bomb itself was likewise a marvel of DIY design and construction. The device consisted of two parts: a triple-banded metal collar with four keyholes and a three-digit combination lock, and an iron box containing two 6-inch pipe bombs loaded with double-base smokeless powder. The hinged collar locked around Wells' neck like a giant handcuff. Investigators could tell that it had been built using professional tools. The device also contained two Sunbeam kitchen timers and one electronic countdown timer. It had wires running through it that connected to nothing—decoys to throw off would-be disablers—and stickers bearing deceptive warnings. The contraption was a puzzle in and of itself.

The most perplexing and intriguing pieces of evidence, though, were the handwritten notes that investigators found inside Wells' car. Addressed to the "Bomb Hostage," the notes instructed Wells to rob the bank of $250,000, then follow a set of complex instructions to find various keys and combination codes hidden throughout Erie. It contained drawings, threats, and detailed maps. If Wells did as he was told, the instructions promised, he'd wind up with the keys and the combination required to free him from the bomb. Failure or disobedience would result in certain death. "There is only one way you can survive and that is to cooperate completely," the notes read in meticulous lettering that would later stymie handwriting analysis. "This powerful, booby-trapped bomb can be removed only by following our instructions... ACT NOW, THINK LATER OR YOU WILL DIE!" It seemed that whoever planned the robbery had also constructed a nightmarish scavenger hunt for Wells, in which the prize was his life.

In the frantic hours after Wells was killed, the cops tried completing the hunt themselves. The first note was straightforward enough: "Exit the bank with the money and go to the McDonald's resturaunt [sic]," it read. "Get out of the car and go to the small sign reading drive thru/open 24 hr in the flower bed. By the sign, there is a rock with a note taped to the bottom. It has your next instructions." Wells drove straight there after he left the bank with the bag of cash. He retrieved a two-page note from the flower bed, which directed him up Peach Street to a wooded area several miles away, where a container with orange tape would hold the next set of instructions. Wells was caught before he got to that clue, but the investigators picked up the thread, locating the container with the orange tape. In it, they found a note directing them 2 miles south to a small road sign, where the next clue would be waiting in a jar in the woods nearby. When they got there, they found the jar, but it was empty. Whoever had set this macabre ordeal in motion, it seemed, had called it off once the cops had appeared—and had probably been watching them every step of the way.

Wells' clothing added another layer of intrigue. He died wearing two T-shirts, the outer one emblazoned with a Guess clothing logo. Wells wasn't wearing the shirt at work that morning, and his relatives said it wasn't his. It appeared to be a taunt: Can you guess who is behind this?

That was just one of the questions that perplexed investigators. What, for instance, was the purpose of the scavenger hunt? Why send a hostage hopping around Erie in broad daylight? Why scatter clues in public locations where they might be discovered? How was Wells chosen to be the hostage?

The bomb was rigged such that any attempt to remove it would set it off.

Photo: Erie Federal Courthouse; Erie Bureau of Police; Newscom

The riddles transfixed the city of Erie and drew headlines in newspapers from St. Louis to Sydney. It also set in motion a byzantine investigation, with federal agents sniffing out clues and hunting down leads in twisted pursuit of the shadowy criminal who came to be known as the Collar Bomber. For seven years, the FBI was engaged in a scavenger hunt of its own, one that the Collar Bomber seemed to have planned as intricately as the one that had ensnared Wells. The only question was whether the Feds would get any further than Wells had.

The hunt began at Mama Mia's Pizza-Ria. That's where Wells was working at 1:30 pm on the day of the robbery, when an order came in for two small sausage-and-pepperoni pies to be delivered to a location on the outskirts of the city. Wells was a loyal employee—in 10 years, the only time he had called in late for work was when his cat died. Even though he was at the end of his shift, he agreed to deliver the order. He walked out of the shop, two pies in hand, at about 2 pm.

Wells entered the bank with this ingenious handmade gun disguised as a cane.

Photo: Michael Schmeling

The delivery location, reachable only by a dirt road, was a TV transmission tower site in a wooded area off of busy Peach Street. When investigators combed the vicinity, they discovered shoe prints consistent with Wells' footwear and tire tracks matching the treads on his Geo Metro. But the site offered no clues as to who may have lured him there or what happened once he arrived.

The next day, a reporter and a photographer for the Erie Times-News headed to the tower. The dirt road leading there was cordoned off by authorities, but the journalists spotted a tall, heavyset man in denim Carhartt overalls pacing in front of a home that sat right next to it. His backyard extended almost to the transmission tower. The man identified himself as Bill Rothstein.

Rothstein, 59, was an unmarried handyman and a lifelong resident of the area. He spoke elegantly, like someone who takes great pride in his mastery of the English language. (He was also fluent in French and Hebrew.) Rothstein seemed oblivious to the investigation unfolding beyond his backyard. The journalists, eager to get a view of the scene, asked Rothstein if he could lead them through his yard. He agreed. They headed into the thick brush but still couldn't see much. After spending about 15 minutes at Rothstein's place, they took off.

Bill Rothstein may have appeared to be just a man who owned a house next to a TV tower. But he turned out to be hiding a dark secret. On September 20, less than a month after the bomb killed Wells, Rothstein called 911. "At 8645 Peach Street, in the garage, there is a frozen body," he told the police dispatcher, referring to his own address. "It's in the freezer."

Within hours of making the call, Rothstein was in custody. He told the cops that he had been in agony for weeks. He had considered killing himself, he told them, and had gone so far as to write a suicide note, which investigators found inside a desk at his home. Writing in black marker, Rothstein expressed his apologies "to those who cared for or about me," identified the body in his freezer as that of Jim Roden, and noted that he "did not kill him, nor participate in his death." The note opened with a curious disclaimer: "This has nothing to do with the Wells case."

Bill Rothstein was a handyman with the skills to fabricate an elaborate explosive device.

Photo: Erie Federal Courthouse; Erie Bureau of Police; Newscom

Over the next two days, Rothstein explained to police how a dead man came to be in his freezer. In mid-August, he said, he'd received a phone call from an ex-girlfriend, Marjorie Diehl-Armstrong, whom he had dated in the 1960s and early 1970s. Diehl-Armstrong told him she had shot her live-in boyfriend, James Roden, in the back with a Remington 12-gauge shotgun, in a dispute over money. Now she needed help removing the body and cleaning up the scene inside her Erie home, about 10 miles from Rothstein's place. Rothstein did what she asked. He kept the corpse in a chest freezer in his garage for five weeks. He painstakingly melted down the murder weapon and scattered the pieces around Erie County. But, Rothstein said, he couldn't go through with the plan to grind up the body, and he called 911 because he was afraid of what Diehl-Armstrong might do to him.

On September 21—the day after Rothstein called 911—Diehl-Armstrong was arrested for the murder of Roden. Sixteen months later, in January 2005, she pleaded guilty but mentally ill and was sentenced to seven to 20 years in state prison. But by that time, Rothstein was past caring about the old girlfriend he'd given up to the cops: He had died of lymphoma in July 2004.

The team of federal agents investigating the collar bomb mystery hadn't been paying much attention to the Roden murder. It was a local matter and seemed to have nothing to do with their case. But in April 2005, they got a phone call from a state police officer who had just met with Diehl-Armstrong about an unrelated homicide. Rothstein's suicide note, it seemed, was a lie; Diehl-Armstrong had said that Roden's murder had everything to do with the collar bomb plot. When the Feds met with Diehl-Armstrong, she told them that, if they could arrange a transfer from Muncy state penitentiary to the minimum-security prison in Cambridge Springs, a facility much closer to Erie, she would tell them everything she knew.

Even before she was arrested for killing Roden, Diehl-Armstrong was one of Erie's most notorious figures, well known for her string of dead lovers. She first drew public attention in 1984 when, at 35, she was charged with murdering her boyfriend, Robert Thomas. Diehl-Armstrong claimed she shot him six times in self-defense, and a jury eventually acquitted her. Four years later, her husband, Richard Armstrong, died of a cerebral hemorrhage. The death was ruled accidental, but questions lingered; Armstrong had a head injury when he arrived at the hospital, but the case was never forwarded to the coroner's office.

Back in high school, according to former classmates, Diehl-Armstrong was known for her dazzling intelligence, and she still possessed an almost encyclopedic knowledge of literature, history, and the law. But over the years, that brilliance had become spiked with madness. According to court records, she suffered from bipolar disorder. Her moods swung sharply, and she appeared unable to control her nonstop, rapid-fire speech. She was paranoid and narcissistic. In 1984, investigators found 400 pounds of butter and more than 700 pounds of cheese, nearly all of it rotting, inside her trash-strewn house. Psychiatrists deemed her mentally incompetent seven times before a judge finally ruled she was fit to be tried in the Thomas case.

She seemed to be exactly the kind of person—murderous, eccentric, and intent on demonstrating her intellectual gifts—who might devise an overly complicated bank heist. She also seemed to be the kind of person who would likely be unable to stop herself from telling the world about her brilliant ruse.

Evidence collected over the course of the complex investigation: a Remington shotgun shell.

Photo: Michael Schmeling

When Diehl-Armstrong met with federal investigators for a series of interviews, that's exactly what she appeared to be doing. While she insisted that she was not in any way involved in the plot, she admitted that she knew about it, that she had supplied the kitchen timers that were used in the bomb, and that she was within a mile of the bank at the time of the robbery. She also said that Wells, the dead pizza delivery guy, was not just a victim but had been in on the plan. And so was Rothstein, the man who turned her in for Roden's murder. In fact, she asserted, he had masterminded the whole thing.

But even as Diehl-Armstrong pointed the finger at Rothstein, she was implicating herself. Indeed, even before hearing her self-incriminating testimony, investigators had begun to suspect that Diehl-Armstrong was behind the collar bomb plot. Over the previous weeks, they had met with four separate informants who revealed that Diehl-Armstrong had talked about the crime in intimate detail. One kept notes of the conversations, which included Diehl-Armstrong's assertions that she killed Roden because "he was going to tell about the robbery" and that she had helped measure Wells' neck for the bomb.

Then, in late 2005, a few months after Diehl-Armstrong first talked to the Feds, they received another break in the case: A witness came forward to say that an ex-television repairman turned crack dealer named Kenneth Barnes was also involved. Barnes, an old fishing buddy of Diehl-Armstrong, had spoken too freely about the plan, and his brother-in-law had turned him in while Barnes was already in jail on unrelated drug charges. Threatened with even more time behind bars, Barnes agreed to a deal: He would give a full account of the crime in exchange for a reduced sentence.

Barnes confirmed the Feds' belief that Diehl-Armstrong was the mastermind behind the collar bomb plot. He claimed she needed the cash so that she could pay him to kill her father, who she believed was blowing through his fortune—money she expected to inherit. Barnes insisted he was kept in the dark about several aspects of the plot. But even with holes, his account corroborated much of what the agents had already heard. The investigation, finally, was gaining steam.

On February 10, 2006, federal agents met again with Diehl-Armstrong, who had brought her attorney. The agents told Diehl-Armstrong they had enough evidence to bring an indictment against her. She went ballistic, slamming her fist on a conference table and cursing out the agents and her lawyer. But, incredibly, she continued to speak with them. In a subsequent meeting, she even agreed to drive around Erie with them to point out where she was the day Wells robbed the bank. At the conclusion of the drive, in which she admitted to being at several locations linked to the crime, Diehl-Armstrong told the agents she wouldn't provide any more information without receiving an immunity letter. It was too late. The woman who couldn't stop talking had already said far too much.

In July 2007, a month shy of the four-year anniversary of Wells' death by collar bomb, the US attorney's office in Erie called a news conference about "a major development" in the case. Standing before a bank of TV cameras, US attorney Mary Beth Buchanan announced that the investigation was over. Diehl-Armstrong and Barnes were charged with carrying out the sensational crime—a plot that Diehl-Armstrong had put into motion. The indictment also charged that other conspirators were involved. Rothstein was one. And Wells, the purported victim, was another. Pulling together information culled from more than a thousand interviews over almost four years, the indictment charged that Wells was in on the scheme from the beginning. He had agreed to rob the bank wearing what he thought was a fake bomb. The scavenger hunt, he was told, was simply a ruse to fool the cops; if he got caught, he could point to the menacing instructions as evidence that he was merely following orders.

But over time, Buchanan said, Wells went from being a planner to "an unwilling participant." At some point, instead of merely playing the part of a hostage, Wells was double-crossed and actually became one. The fake bomb turned out to be a real one. And the scavenger hunt went from a clever piece of misdirection to a real-life race against the clock. Sitting in the press section, Wells' family seemed stunned. One of his sisters, Barbara White, repeatedly shrieked "Liar!" as Buchanan completed her statement.

Wells' relatives weren't the only ones who were dubious. For those who closely tracked the case, the government's long-awaited announcement was severely unsatisfying. It seemed to provoke as many questions as it answered. Why would Wells participate in such a plot? Did he realize the danger that he was in? And could Diehl-Armstrong, with her myriad mental issues, really plan such a complex crime? The questions only multiplied a week later, when it was revealed that the FBI had concluded that the entire scavenger hunt was a hoax. The bomb was rigged such that any attempt to remove it would set it off. Wells was destined to die.

Barnes pleaded guilty in September 2008 to the conspiracy and weapons charges involved in the collar bomb plot. He was sentenced to 45 years behind bars, but he agreed to testify against Diehl-Armstrong in the hope of getting his sentence reduced.

More evidence collected over the course of the investigation (from left): a component from the collar bomb and directions leading the doomed victim to an orange-taped container in the woods.

Photo: Michael Schmeling

Marjorie Diehl-Armstrong's brilliance had become spiked with madness. Paranoid and narcissistic, her moods swung sharply and she appeared unable to control her nonstop, rapid-fire speech.

Photo: Erie Federal Courthouse; Erie Bureau of Police; Newscom

Diehl-Armstrong's trial promised to clear up the mysteries that had surrounded the collar bomb case. But those revelations would have to wait. First a federal judge ruled Diehl-Armstrong mentally unfit to stand trial. When she finally was deemed ready to face a judge and jury, she was diagnosed with glandular cancer, and the proceeding was put on hold again as she awaited her prognosis. The judge received the doctors' assessment in August 2010: Diehl-Armstrong had three to seven years to live. Prosecutors opted to press on, and the trial was rescheduled for October 12.

Most intriguing, Diehl-Armstrong's lawyer, Douglas Sughrue, had decided to let his client take the stand. It seemed to be a risky move. After all, she had already implicated herself in the murder. Was it wise to let such an erratic, unpredictable personality testify?

On day five of the trial in the Erie Federal Courthouse, Ken Barnes took the stand. By this time, the prosecutor—Marshall Piccinini, a fast-talking, silver-haired assistant US attorney—had already built an impressive case. Summarizing the strange characters linked to the Wells plot as a cast of "twisted, intellectually bright, dysfunctional individuals who outsmarted themselves," Piccinini had trotted out seven former inmates who recounted incriminating information that Diehl-Armstrong had shared with them. Barnes—the ex-crack dealer and would-be hit man—was Piccinini's star witness, and his final one. He was also the man who seemed prepared, finally, to tell the whole story of what happened in the days leading up to August 28, 2003, the day of the robbery. Barnes, who had the wan face and sparse collection of teeth of the former crack addict he was, approached the bench and took the oath. Then he sat in the witness box and matter-of-factly described the conspiracy to a rapt jury.

Diehl-Armstrong, Barnes said, devised the plan and enlisted a few coconspirators to help carry it out. Rothstein was one of them. Wells was another, lured in with the promise of a payday. He certainly needed the money. It turned out that the quiet pizza man had a relationship with a prostitute. With the help of his pal Barnes, he bought crack, which he then gave to the prostitute in exchange for sex. But in the weeks before the robbery, Wells fell into debt with his crack dealers and needed cash. It was only on the afternoon of the crime, when he delivered the pizzas to the TV transmission tower, that Wells realized he had been double-crossed and that the bomb was real. He was tackled as he tried to sprint away and locked into the device at gunpoint.

Throughout Barnes' testimony, Diehl-Armstrong angrily whispered to her attorney. Several times she blurted out "Liar!" drawing stern warnings from the judge. To all appearances, it was excruciating for her to listen to people like this discredit her.

On October 26, the eighth day of the trial, Diehl-Armstrong finally got the opportunity to tell her version of events. For five and a half hours over two days, she used the witness stand as her stage. Her wavy black hair looked greasy and clung to the sides of her face. Every time she opened her mouth, she unleashed a torrent of words. She ridiculed her lawyer: "That's a stupid question, Mr. Sughrue." She belittled the prosecutor: "If this is the kind of evidence you have against me, I'm telling you, this is a pitiful case." She cried. She yelled. More than 50 times, the judge sought—often futilely—to cut her off.

During her first day on the stand, she mentioned Brian Wells only once, in the final 10 minutes of a nearly 100-minute-long diatribe: "I never met Brian Wells, and I never knew Brian Wells. Never. I became aware of him the day that he died. I saw it on the news."

The jury didn't buy it. After deliberating for 11 hours, the seven women and five men returned guilty verdicts on all three charges: armed bank robbery, conspiracy, and using a destructive device in a crime of violence. She could face a mandatory life term when she is sentenced on February 28.

After seven years, the outstanding questions had finally been answered. At least, that's how most observers viewed Diehl-Armstrong's conviction. But that's not how Jim Fisher sees things. A retired FBI criminal investigator, Fisher started closely tracking the collar bomb case after he saw footage of Wells squirming on the pavement with the device yoked around his neck. The then-64-year-old criminal justice professor had a thing for unsolved crimes, and this was one of the most staggering he had ever seen. He obsessively pored over the media coverage of the case and studied every piece of evidence released by the FBI. And, according to Fisher, there is no way that Marjorie Diehl-Armstrong planned the collar bomb caper.

For proof, Fisher points to a profile of the Collar Bomber produced by the FBI's Behavioral Analysis Unit. "It continues to be the opinion of the [department] that this is much more than a mere bank robbery," it reads. "The behavior seen in this crime was choreographed by 'Collarbomber' watching on the sidelines according to a written script in which he attempted to direct others to do what he wanted them to do... Because of the complex nature of this crime, the [FBI's Behavioral Analysis Unit] believes there were multiple motives for the offender, and money was not the primary one." In other words, the robbery was never the point. Whoever planned the heist didn't care whether Wells ever delivered the cash. They just wanted to craft a beguiling puzzle, one that would resist explanation for years to come and that would keep cops and investigators hunting fruitlessly after clues just as Wells was sent on his doomed scavenger hunt.

None of this, Fisher says, sounds much like Diehl-Armstrong, who prosecutors credited with planning the whole affair in order to get enough money to pay a hit man. But if Diehl-Armstrong didn't set this plan in motion, who did? Fisher turns back to the FBI's profile, which states that the bomb builder was "comfortable around a wide variety of power tools and shop machines." He was "a frugal person who saves scraps of sundry materials in order to reuse them in various projects." And he was "the type of person who takes pride in building a variety of things."

To Fisher, that sounds like a description of Bill Rothstein, the man who lived next to the TV tower and who agreed to keep a dead man in his garage freezer. The handyman had the skills to fabricate such an elaborate explosive device. Even more convincing to Fisher was the description of the mastermind directing others according to a written script that only he seemed to have access to.

In Fisher's view, Rothstein toyed with the investigators from the start, concocting the scavenger hunt at least in part to send them on a useless chase, eating up valuable time in the precious days after the robbery. Then there was the 911 call. Fingering Diehl-Armstrong in the Roden murder case allowed Rothstein to frame the Wells investigation on his own terms. If he hadn't gone to the Feds, he knew, Diehl-Armstrong or one of his coconspirators would have. So he implicated Diehl-Armstrong in the Roden case before she could rat him out, all while pleading ignorance of the collar bomb affair. He also gave the impression that he was a man with nothing to hide. After all, why would someone who was involved in the plot voluntarily call the cops and meet with them for hours? Rothstein continued to deny any knowledge of the collar bomb plot on his deathbed, even though he seemingly had no more reason to hide. Until his dying day, Rothstein was insulating himself, or in Fisher's words, "controlling the narrative."

In his closing argument at Diehl-Armstrong's trial, the prosecutor, Piccinini, described the crime as a "ludicrous, overwrought, overworked, desperately failed plan." If stealing money was the ultimate goal, then that's a pretty accurate summary. But Fisher thinks that this wasn't about money. Rothstein, who never accomplished much in life, wanted to prove his brilliance by executing a crime that would grab headlines across the globe and baffle authorities for years. He recruited coconspirators he knew he could control and kept crucial details of the plot from them—a tactic designed to further complicate the investigation.

"The son of a bitch ended up winning," Fisher says. "He died with all of the secrets. He died taking all the answers with him. He gets the last laugh in that sense. He escaped punishment. He escaped detection. He left us with these idiots and a bunch of questions."

Those questions, Fisher says, serve as a reminder of Rothstein's ultimate triumph. He died a free man. And the last step in the scavenger hunt, the clue that reveals the answers that the agents had been searching for all along, will forever remain hidden.

Rich Schapiro (richschapiro@gmail.com) is a writer based in New York City. This is his first article for WIRED.

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