He was supposed to be an angel of mercy — but he was an angel of death, and likely the most prolific serial killer America has ever seen.



Charles Cullen had most recently been a nurse at Somerset Medical Center in New Jersey when he was arrested for killing patients with drug cocktails he secretly administered. He confessed to 40 murders in New Jersey and Pennsylvania — though investigators believe he may have killed as many as 400. He is currently serving 17 life sentences.

It was never revealed how detectives were able to stop him — until now. In a new book, “The Good Nurse,” author Charles Graeber unveils the identity of a confidential informant, Amy Loughren, who cracked the case.

Loughren was another nurse at Somerset, a co-worker and confidant of Cullen. Contacted by detectives, Loughren agreed to provide them files from the hospital, wear a wire to try to get him to confess, even talk to him in the interrogation room.

It was Loughren who first realized the scope of Cullen’s madness. This exclusive excerpt reveals the chilling moment, in November 2003, that Amy Loughren discovered how Cullen was picking — and killing — his victims.

Amy found curious combinations of drugs that Charlie had consistently ordered. The list was long, sometimes half a dozen in a night. Amy knew these drugs to be more commonly used in a cardiac unit. Charlie was working in intensive care. His orders emptied the supply drawers.

Then, time and time again, Charlie ordered a restock from the pharmacy. His position meant he’d be the first to take the delivery. At the time, he was seen as being helpful. Now Amy wasn’t so sure.

The two Somerset detectives who had contacted her, Tim Braun and Danny Baldwin, were investigating the deaths of a handful of patients who had suspicious levels of a heart drug called digoxin in their systems.

HOW HERO NURSE GOT CHARLES CULLEN TO CONFESS

Detectives were trying to trace a single gun; Amy thought this was pointing to an entire arsenal.

Charlie had been bartending, titrating a pharmacopoeial mélange, from both drugs he’d pulled from the cabinet and drugs he hadn’t.

Each drug in the cocktail had a specific biochemical effect. Together, they were a biochemical symphony. In combination, it didn’t require nearly so much of any one drug to push a vulnerable patient over the edge. One drug pushed while the other pulled.

Only the patient’s reaction mattered. The gap of time between the serving of the cocktail and the patient’s reaction was suspenseful. There might be a crash or a code or a Lazarus-like recovery. The cocktail was the riddle and the lab reports were the answer.

Amy had imagination enough to make sense of the patterns, but she couldn’t begin to imagine the monster that amused itself with them. All she was certain of was that it wasn’t the same gentle soul who was her friend Charlie. The emotional disconnect bothered her as much as the murders themselves.

Amy considered herself to be a perceptive person — a spiritual traveler, a listener with well-tuned antennae for the frequency of vibes. Growing up as she did, she had always assumed that if she was near a monster, she would feel it. And yet, standing next to Charlie, she had never felt anything like evil.

Maybe she’d gotten him wrong, or maybe her antennae were broken. Or maybe, Amy thought, she was half blind and could see only the good in people.

Somerset used a computer system for keeping track of patients called Cerner. Charlie’s Cerner pages told her she had assumed wrong. Charlie was not, actually, the world’s greatest nurse, the world’s greatest chart keeper Amy had ever seen. He had hardly typed a line.

It was, in fact, the worst charting Amy had ever seen. There were blotches of words here and there, blurts, spasms of hurried and misspelled observations. It couldn’t have taken him more than a minute to do that work. Whatever he was doing on the computer, it wasn’t input. That meant Charlie had been outputting something.

Amy had to wait until her next shift to print out the rest of the records. This time, she couldn’t wait until she got home. That morning she called ahead, then brought her paperwork to the second floor of the prosecutor’s office to share her discovery with the detectives.

The Cerner automatically kept track of everything a nurse did within the system and provided a time and date stamp of every page a nurse had browsed. Charlie was browsing all night. That was what he was doing. Browsing.

Cullen’s computer records were the most incriminating piece of evidence the Somerset County Prosecutor’s Office had against him thus far. But in order for the detectives to understand it, Amy needed to provide a quick primer.

Cerner had been introduced to the medical profession only a few years before as a compact and efficient way to input notes on patients, to look up their allergies, code status, lab values, etc.

But nurses were only supposed to do that for the patients they were caring for on shift.

What nurses never did, at least not any nurses Amy had ever known, was use Cerner to look up the status of other nurses’ patients. But that, it seemed, was exactly what Charlie Cullen had been doing.

Amy started with Charlie’s June forays into the chart of one patient, the Rev. Florian Gall. The hospital records showed that Gall had gone into cardiac arrest at 9:32 a.m. on the morning of June 28 and died approximately 45 minutes later.

Gall was not Cullen’s assigned patient on the night he died. Yet the Cerner records showed Charles Cullen snooping into Gall’s medical chart at 6:28 a.m., then again at 6:29 a.m. on June 28. He was checking in, only minutes apart, looking for something only a half-hour after a digoxin spike had registered in Gall’s lab work and three hours before the digoxin levels in Gall’s system would stop his heart.

“And that’s just Gall,” Amy said. The Cerner records contained lines and lines of Charlie Cullen’s log-ins at the computer, thousands of them, sometimes hundreds a night.

“He was studying them,” Danny said. “Why the f— was he studying them?”

Amy thought she knew. The nurses had IV bags lined up for them. But what if Charlie had made a drug cocktail, and injected it into one or more of the IV bags sitting by where he worked?

He wouldn’t need to bring them to the patient’s rooms, he wouldn’t need to be present at all. The other nurses — even Amy — would do that work for him. Charlie could simply retreat to his corner and use the Cerner to scan the lab reports and the patient’s progress.

Cerner would tell him where his loaded IVs landed. He wouldn’t need to be present for the death to feel the impact; you could just scan back on the Cerner anytime and follow the action.

It could be that same night or the next day, it didn’t matter; the event was always available on the screen to be relived again and again.

Was that what he was doing? Amy felt her heart beginning to sicken. She had delivered his drug cocktails.

And her friend Charlie had been following the action across the ward, like the box scores on a sports page.

Excerpted from “The Good Nurse: A True Story of Medicine, Madness, and Murder” (Twelve), by Charles Graeber, out tomorrow.