On September 9, 1965, Navy Cmdr. James Bond Stockdale was flying his A-4 Skyhawk on a mission over North Vietnam, just days after the Gulf of Tonkin incident, when his plane took fire and hurtled down. Forced to eject with seconds to spare, he landed with severe injuries: his left leg bent sideways by 60 degrees and his kneecap smashed; his left shoulder dislocated, rendering his arm useless; his back, he thought, likely was broken.

Stockdale was quickly discovered by villagers, who beat him and dragged him through the streets until he was delivered to his ultimate destination: the Hoa Lo prison, or, as it was derisively known among the American POWs held there, the Hanoi Hilton.

Twenty-five months later, Stockdale — who, as CAG (Commander of the Air Group) was the highest-ranking naval officer in captivity — would be moved, along with 10 other American POWs, to an even more remote prison site they called Alcatraz.

Together, these men were regarded by the Vietnamese as the most dangerous, subversive and indestructible Americans they had ever encountered. Their plan: By isolating them from the other POWs — and each other — they would finally maintain some control over these most insolent American soldiers.

Things did not go according to plan.

On Feb. 11, 1965, Lt. Cmdr. Bob Shumaker became the second US pilot shot down over Vietnam. He was taken to the Hanoi Hilton and held in isolation for four months before he was even allowed to write home.

In that time, Shumaker — known as “Shu” — made contact with one other POW. Shu had seen another American regularly dumping his slop bucket outside and managed to scratch out a note on a piece of toilet paper.

“Welcome to the Hanoi Hilton,” he wrote. “If you get note, scratch balls as you’re coming back.” Shu then smuggled the note into a crack in a wall near the latrine, and just a few minutes later, his fellow American walked through the courtyard, furiously scratching his crotch. He’d managed to leave a reply: He was Ron Storz, captain USAF.

As more American POWs arrived, Shu realized that the Vietnamese would soon isolate them. How could they keep communicating? Morse code was no good — even the North Vietnamese understood that. Then he recalled a tap code developed by American POWs in Korea, one he’d learned in Air Force Survival, Evasion, Resistance and Escape School.

This was how the Americans at Hanoi, led by Stockdale, would communicate from now on: They could warn each other about the most sadistic guards, check in with each other, relay what to expect in so-called “interrogations,” encourage each other not to break, offer consolation when, one by one, they eventually did.

There was Harry Jenkins, a 6-foot-5 Navy pilot who refused to give up what his father did for a living — once they got that, they’d want more and more. Jenkins was tortured so brutally, he was sure he’d lose his hands. He passed out, and when he came to, his tormenters hung him from his wrists — still tied behind his back — from a meat hook. He had never conceived of such pain. He asked God to take him.

Again, Jenkins passed out. When he came to again, he was made to kneel on gravel for hours, and only when the skin was sheared from his kneecaps did he submit.

“My father grows flowers,” he said.

The torture was constant. The Americans were thrown in tiny cells, slabs of concrete for beds, single, bare lightbulbs making sleep impossible. They were in a constant state of starvation, and when they were fed, their watery soup was laced with pebbles or feces. They were made to stand on stacked stools for days on end. They were often strapped down by 15-pound leg irons, which caused lacerations and infection, or by stocks at the ends of their beds, which kept them on their backs for days. The walls and floors were overrun with roaches and rats. When they were strapped down, they were forced to lie in their own excrement.

Jim Stockdale, who’d been held in solitary for 18 months, worried when he saw the Vietnamese begin to soften toward their prisoners. The beatings lessened, the food increased. This was equally dangerous, and could cause POWs to submit: to confess to war crimes, to be used as propaganda, to give up fellow soldiers in exchange for early release — the “Fink Release Program,” Stockdale called it.

Stockdale’s second-in-command was Cmdr. Jerry Denton, who had been hauled before TV cameras by the North Vietnamese and had blinked “t-o-r-t-u-r-e” in Morse code on the air.

There was Nels Tanner, tortured into writing a confession of war crimes; he identified a Lt. Clark Kent and was thereafter known as the author of Superman’s confession.

While transported to Hanoi after being shot down, Jim Mulligan’s captors poured gasoline over his bound arms, fusing threads of rope into his wounds. Howie Rutledge was beaten mercilessly during his first day in captivity; refusing to give up his ship and squadron, he was told to get on the floor, and a guard thrashed his injured and dislocated leg until it pressed flat on the ground.

He and Sam Johnson had both suffered over 60 boils each during one summer, and Johnson had been held in solitary multiple times, often going six days in a row without sunlight.

Ron Storz had been made to stand on a stool for seven days straight, beaten nearly to death by a bamboo stick. Hands tied behind his back, George McKnight was held for 34 nights in an air-raid trench 4 feet long; he was 6-foot-2.

He would conspire with POW George Coker, and together they’d make a daring escape from the Hanoi Hilton in 1967, getting 15 miles before they were discovered by villagers on a riverbank.

Together, these 11 men were the most unbreakable prisoners at the Hanoi Hilton. So the Vietnamese moved them to a remote outpost, the one the POWs called Alcatraz.

Here, in a small structure near the Ministry of National Defense, the Alcatraz 11 were each thrown, one by one, into windowless rooms. Stockdale and Mulligan were considered so dangerous that the Vietnamese left an empty cell between them, to thwart any secret communication.

It didn’t work. Mulligan scratched audible messages while he was at the latrine. The two men, isolated from the other nine, figured out that they could flash hand signals through camp in the gap between the door and the floor.

These messages were often no more subversive than “How you doing?” — words of solace or encouragement. Sometimes, they would tap codes to signal group prayer, or the Pledge of Allegiance, which they’d whisper simultaneously.

Despite increased isolation, starvation and torture, the men remained determined. By spring 1968, the men had spent five months at Alactraz, and the cells were becoming sweatboxes, reaching up to 110 degrees each day. The combined stench of human waste and sweat made it nearly impossible to breathe.

Yet Stockdale and Denton refused to capitulate. Instead, they ordered their men to join in a hunger strike. Denton was soon called to meet with a commander they’d dubbed Rat.

“I want to congratulate you,” Denton said, “on putting us to a slow death by heat.”

“No, Denton,” Rat said. “I did not know conditions were that bad. Our orders are to keep you isolated and in irons. We have no orders to kill you. We will study.”

That did not mean an end to the torture, yet the men remained united. On the third anniversary of his capture, Stockdale found a message at the latrine, which read in part, “We love you.”

Two months later, after Nixon was elected, the Vietnamese wanted real propaganda out of the Alcatraz 11. They beat George McKnight for 36 hours straight; they beat and tortured Denton so brutally his arms turned black; Jim Mulligan was strung up and beaten for six days, Nels Tanner for 17. Sam Johnson was so brutalized that when he finally submitted, he literally could not write the apology demanded by the Vietnamese.

He was able only to sign it, and when he was thrown back in his cell, he heard Jerry Denton whispering to him from next door.

“Sam, Sam, it’s OK, buddy.”

“I made them write it, Jerry,” he replied. “But I had to sign it.”

“It’s OK, Sam,” Jerry said. “You’re OK. Hang on, You did good.”

Each of the men would break, and each of the men understood. In fact, all of them worried most about Ron Storz, who had now been in solitary for four years and had tried to commit suicide with a razor. Jerry Denton urged Storz to say whatever he had to so he could get out: His life was in danger, and it wasn’t a violation of the military’s Code of Conduct.

Storz was too far gone to take it as anything but an insult. Of the 11, he was the only one who wouldn’t make it back. He died in captivity.

On Dec. 9, 1969, after 25 months, the POWs were taken out of Alcatraz and transported back to the Hanoi Hilton. By now, the families of POWs had brought enough publicity to the cause — forcing the US government to address it — that the North Vietnamese did not want to be caught violating the Geneva Conventions.

After leaving Alcatraz, some of the men thought they’d be going home within days, weeks or maybe months. They were not freed until Feb. 12, 1973, two weeks after the Paris Peace Accords. Sam Johnson and Jim Mulligan flew home on the same C-141, and once on board, Mulligan dissolved into tears.

A nurse gently approached. “It’s OK, Captain Mulligan,” she said. “It’s all over with, and we are going to take you home.”

Not only did every Alcatraz survivor go on to have a full and happy life, several continued to serve the country that had sent them into this misguided war. Tanner, Jenkins, Rutledge, Mulligan, Coker, McKnight and Johnson went back to active duty; Johnson has served in Congress since 1991.

In 1988, Shumaker retired as rear admiral from the Navy. Denton, too, made rear admiral, and served in the US Senate from 1981-87. Stockdale was awarded the Medal of Honor in 1976, ultimately retiring as vice admiral. In 1992, he ran for vice president on the ticket with Ross Perot.

He died on July 5, 2005, after suffering from Alzheimer’s. In 2009, the surviving members of the Alcatraz 11 commissioned the USS Stockdale, a guided missile carrier that bears the motto “Return with honor.”