“It was just like wildfire. Everyone was jumping into the game.”

In the early afternoon of November 29, 1983, the Los Angeles field office of the Federal Bureau of Investigation received a call from a Bank of America branch in the Melrose District. The call was taken by an FBI agent named Linda Webster. She was the person in the office who fielded what were known as 2‑11s: reports of bank robberies. There had just been a holdup, she was told. The suspect was a young white male wearing a New York Yankees baseball cap. Slender. Polite. Southern accent. Well dressed. He said please and thank you.

Webster turned to her colleague, William Rehder, who ran the FBI’s local bank- robbery division.

“Bill, it’s the Yankee.”

The Yankee Bandit had been active in Los Angeles since July of that year. He had hit one bank after another, slipping away each time with thousands of dollars in a leather suitcase. Rehder was growing frustrated. Who was this man? All the Bureau had to go on was that telltale baseball cap. Hence the nickname: the Yankee Bandit.

Half an hour passed. Webster got another 2‑11. This one was from a City National Bank sixteen blocks west, in the Fairfax District. They had been taken for $2,349. The caller gave Webster the details. She looked at Rehder.

“Bill, it’s the Yankee again.”

Forty- five minutes after that, the Yankee hit a Security Pacific National Bank in Century City, then immediately walked one block down the street and held up a First Interstate Bank for $2,505.

“Bill, it’s the Yankee. Twice. Back to back.”

Less than an hour passed. The phone rang again. The Yankee had just hit an Imperial Bank on Wilshire Boulevard. If you drive from Century City to the Imperial Bank on Wilshire, you pass right by the FBI’s office.

“He probably waved at us,” Rehder told Webster.

They were now on notice. History was being made. They waited. Could the Yankee possibly strike yet again? At 5.30, the phone rang. An unknown white male – slender, Southern accent, Yankee cap – had just robbed the First Interstate Bank in Encino, fifteen minutes north on the 405 freeway, for $2,413.

“Bill, it’s the Yankee.”

One man. Four hours. Six banks.

“It was a new world’s record,” Rehder would write later in his memoirs, “still unbroken.”

No criminal has ever held as exalted a position in American culture as the bank robber. In the years after the Civil War, the country was riveted by the exploits of bands such as the James-Younger gang, who terrorized the Wild West with bank holdups and train robberies. In the Depression, bank robbers became celebrities: Bonnie and Clyde, John Dillinger, “Pretty Boy” Floyd. But in the years after the Second World War, the crime seemed to be fading.

In 1965, a total of 847 banks were robbed across the entire United States – a modest number, given the size of the country. There was speculation that bank robberies were headed toward extinction. Few major crimes had higher arrest – and conviction rates. Banks felt that they had learned how to protect themselves. A definitive 1968 study of bank robbery was entitled “Nothing to Lose,” meaning the act seemed so irrational that its perpetrators must have run out of other options. It seemed like the 20th-century equivalent of cattle rustling. Who does that any more?

But then came an epidemic. In a single year, from 1969 to 1970, the number of bank robberies nearly doubled, then rose again in 1971 and once more in 1972. In 1974, 3,517 banks were robbed. In 1976 the number was 4,565. By the beginning of the 1980s, there were five times more bank robberies than there had been at the end of the 1960s. It was a crime wave without precedent. And it was just getting started. In 1991, the FBI fielded a 2‑11 call from a bank somewhere in the United States 9,388 times.

And the centre of this astonishing surge was the city of Los Angeles.

A quarter of all bank robberies in the United States in those years happened in Los Angeles. There were years when the local FBI office handled as many as 2,600 bank robberies – so many robbers, robbing so many banks, that Rehder and the Bureau were forced to give them nicknames to keep them straight: The man who disguised himself with surgical gauze became the Mummy Bandit. The man who wore a single glove became (naturally) the Michael Jackson Bandit. A two-man team who wore fake moustaches were the Marx Brothers. A short, obese robber was Miss Piggy. A beautiful robber was the Miss America Bandit. A guy who waved a knife was the Benihana Bandit. On and on it went: There were robbers named after Johnny Cash and Robert DeNiro. One group robbed in threes – one dressed as a biker, another as a cop, and the third as a construction worker. Do you need to ask what they were called? This was the 1980s. They were known as the Village People.

“It was just like wildfire,” remembers Peter Houlahan, one of the unofficial historians of the LA bank robbery surge. “Everybody was jumping into the game.”

Ten years into the surge, incredibly, things got much worse. The trigger was the emergence of a two-man group called the West Hills Bandits. The first generation of LA robbers was like the Yankee Bandit: They walked up to a teller, said they had a gun, scooped up whatever cash was on hand, and fled. People called them, a bit dismissively, notepassers. But the West Hills gang went back to the grand tradition of Jesse James and Bonnie and Clyde. They came in hot, in wigs and masks, waving assault weapons. They would force their way into the teller’s cage and clean out the entire bank – empty the vault if they could – before executing a meticulously planned escape. The bandits had a bunker in the San Fernando Valley filled with military-grade weapons and 27,000 rounds of ammunition, to prepare for what their leader believed was an imminent Armageddon. Even by the standards of 1990s Los Angeles, the West Hills gang was a little crazy.

On their fifth robbery, the West Hills crew broke into the vault of a Wells Fargo Bank in Tarzana and made off with $437,000 – more than $1 million in today’s dollars. And then Wells Fargo made a crucial mistake: The bank told the press exactly how much the West Hills gang had stolen. It was like putting a match to kindling. $437,000? Are you kidding me?

Excerpted with permission from Revenge of the Tipping Point: Overstories, Superspreaders and the Rise of Social Engineering, Malcolm Gladwell, Hachette Book Group.