Alcatraz sat a mile and a quarter off San Francisco, close enough for inmates to smell the sea air and hear laughter drifting across the bay. When the Department of Justice took over the island in 1934, it offered no rehabilitation, only containment. Men lived in cells nine feet long, five feet wide, and seven feet high, flushed their toilets with salt water, and were counted 13 times a day. Under the first warden, James A. Johnston, they were also forbidden to speak, a rule that produced paranoia, depression, and hallucinations until it was relaxed in the 1950s.

This episode sets aside the movie myths and looks at how the federal penitentiary actually worked from 1934 to 1963. It covers the oddly excellent food, served to keep the dining hall calm, the pitch black cells of D Block, and the guards’ families who lived a short walk from the cell house. It also explains what really closed the place. Salt water rotted the concrete from within, everything had to arrive by barge, and by 1959 an inmate cost $10 a day to keep there against $3 elsewhere. Attorney General Robert F. Kennedy ordered it shut in 1963.

• Early metal detectors from the Teletouch Corporation kept short circuiting in the salty fog, and the contract was eventually cancelled.
• The cell house corridors were named Broadway, Times Square, and Park Avenue, a constant reminder of the world the inmates had lost.
• Al Capone, who had practically run his previous prison in Atlanta, was reduced to menial labor and played the banjo in the shower block to stay safe. Robert Stroud, the Birdman, kept no birds in his 17 years there.
• Men sent to the hole for 3 to 19 days would throw a uniform button into the dark and crawl around searching for it, just to give their minds a task.
• In 1962 Frank Morris and the Anglin brothers left dummy heads in their beds, dug out their vents with reinforced spoons, and sealed a raft of more than 50 raincoats against hot steam pipes. The U.S. Marshals Service still considers the case open.