Isadore Einstein, known as “Izzy” to his friends, was no one’s idea of a G-man. Short, fat with numerous chins and thinning hair, he was so rotund that the great crime writer, Herbert Asbury, described his belly as moving “majestically ahead like the breast of an overfed pouter pigeon.” With his thick round spectacles perched on his nose, Izzy had all the looks of your below-average Joe. But it was precisely this unprepossessing appearance that would make him, and his similarly schlubby friend, Moe Smith, the greatest federal agents of their age.

That age was Prohibition. It’s a period that nearly 100 years on still seems like a fantastical blip in America’s history. From 1919 to 1933, the Eighteenth Amendment of the United States Constitution declared it illegal to produce, transport or sell alcohol, the result of years of lobbying by the Anti-Saloon League and the Women’s Christian Temperance Union. It had been thought the decree would instill a more peaceable character onto the nation. However those 14 years saw the United States at its loudest, most violent and perversely, most entertaining. It was Prohibition that made the era roar.

When Prohibition went into effect in January 1919, Izzy Einstein lived on New York’s Lower East Side, struggling to keep his wife and four sons fed on a postal clerk’s salary. Reading in the newspaper that the newly created Prohibition Unit was looking for agents, he went down to the local bureau and applied. As Izzy recounted in his wisecracking memoir, Prohibition Agent No. 1, the bureau chief looked him up and down and told him he “wasn’t the type.”

But Izzy was not easily dissuaded. He argued that looking like an everyman was exactly what was needed in this dry new world. Moreover, although he had no gumshoe experience, Izzy insisted he understood people. He had been a salesman and could mix with people and gain their confidence. The bureau chief bought the argument and Izzy was given a badge and thrust out onto the mean streets of New York to sop up the booze that poured through the city’s speakeasies.

A peep hole in the door of a speakeasy during Prohibition. (Credit: Bettmann Archive/Getty Images)

Izzy’s lack of detective training proved to be something of a boon on his first assignment. In order to get a search warrant agents needed proof that alcohol was being sold on the premises. But to get this proof they had to gain access. A notorious speakeasy in Brooklyn had easily spotted any prohibition agents trying to enter. They were not prepared for Izzy, however. He walked up to the joint and banged on the door. A peephole slid open and a gruff voice asked who he was.

“Izzy Einstein,” he responded. “I want a drink.”

“Oh yeah? Who sent you here bud? What’s your business?”

“My boss sent me,” Izzy explained. “I’m a prohibition agent. I just got appointed.”

The door swung open and the doorman slapped him on the back. “That’s the best gag I’ve heard yet.” Once inside the bar, Izzy showed the crowd drinking there his federal badge, leading the bartender to exclaim, “it looks just like the real thing,” which of course it was.

Izzy’s only misstep during his first bust was drinking the whisky he ordered. Physical evidence was needed that a sale of alcohol had been made, and that evidence couldn’t be in an agent’s belly. When he announced himself as a federal agent, the bartender grabbed the bottle of whisky and fled out the back door.

To prevent any further evidence from disappearing, Izzy designed a small funnel to fit into the pencil pocket of his vest. It was connected by tube to a little bottle hidden in the vest’s lining. From then on Izzy would take a sip of the booze he bought, and when the bartender turned his back, would toss the rest of the drink into the funnel. He became so good at this, he boasted, that people standing right behind him did not suspect his sleight of hand. Once “drunk,” Izzy would then go to the restroom, cork the bottle, jot down the name of the bar and the time of sale on its side, and there was the evidence ready to be presented in court.

New York City Liquor Agent Izzy Einstein dumping liquor into the gutter during prohibition. (Credit: Daily News/NY Daily News via Getty Images)

Being himself proved to be Izzy’s masterstroke. There were no less than 20 occasions when Izzy knocked on a speakeasy door, his federal agent badge pinned to his chest, and asked, “Would you like to sell a pint of whiskey to a deserving prohibition agent?” Everyone took him to be a comedian. On other occasions it was his ability to look like an average guy on the street that gained him admission. Speakeasies would open their peepholes to see a fat, short man in dirty overalls mopping his forehead, or carrying a fishing rod, or a pitcher of milk.

Carrying something was, Izzy boasted, often the only trick he needed. A barrel of pickles was a favorite prop because, as he said, “Who’d ever think a fat man with pickles was an agent?”

But sometimes more ingenuity was needed, and with his friend Moe Smith, whom Izzy cajoled into giving up his job as a cigar salesman, Izzy dressed in a series of true-to-life disguises to gain access into speakeasies. “I went after the places that were supposed to be ungettable. And got them,” he wrote.

They drove a coal wagon through the Upper East Side, netting 16 bartenders in one hour. They sold fruit and vegetables in the Bronx and ice in Brooklyn in order to wheedle their way behind the locked doors of illegal bars. They carried thick legal books into booze-serving restaurants frequented by lawyers, and dressed in white coats to gain access to a speakeasy frequented by doctors near Mount Sinai Hospital. On a cold winter night Izzy stood in his shirt-sleeves outside a speakeasy until his teeth were chattering. Moe then half-carried him in shouting, “give this man a drink!” The bartender poured out a shot and Moe booked him.

One time Izzy walked into a restaurant frequented by musicians with a trombone under his arm. He was asked to play a song and performed such a moving rendition of the Prohibition standard, “How Dry I Am,” that the bartender and waiters rushed to pour him a drink and he, thanking them, promptly arrested them. As one contemporary magazine put it, “A day with Izzy would make a chameleon blush for lack of variation.”

New York at the time was awash with booze. Prohibition was largely an idea born in America’s religious rural heartland, and many cosmopolitan city dwellers resented it being imposed on them. Nowhere was this more the case than in New York, the wettest of wet cities, where speakeasies, cabarets and restaurants served alcohol under the protection of corrupt policemen, and a bottle of bathtub gin could be procured at any number of “blind tigers”—storefronts that purported to be pharmacies or fruit stores, but which sold booze under the counter.

Moe Smith (on left in top picture, on right in the bottom one) and Izzy Einstein shown in disguises they used to infiltrate speakeasies. (Credit: Underwood and Underwood/The LIFE Picture Collection/Getty Images)

In many ways, Izzy and Moe were doing the public a service. Much of the booze sold during Prohibition was nasty stuff: denatured ethanol alcohol redistilled, colored and put in a bottle with a fake label. There was also fake scotch made from lice killer, and “squirrel whiskey” made from potatoes, cabbage and old rope.

The bootleggers were ingenious. Izzy and Moe discovered car tires filled with booze, moonshine stills hidden away in old stables, a taxidermied bear stuffed with whisky bottles, and a ring of fake rabbis selling sacramental wine to their supposed congregations. Izzy and Moe were relentless in their work, driven more by the thrill of the chase than their morals. Although they were enforcing an unpopular law, the way they did it was done with such joie de vivre and cleverness that few could begrudge them their job.

The press hung on their every exploit, and wisecracking Izzy and taciturn Moe would tip them off to busts and indulge in ever-crazier deceptions, such as the time they posed as a husband and wife, to bust an illegal liquor joint. One newspaper declared they were “as famous in New York City as the Woolworth building.” But being famous had its setbacks. Soon speakeasies started pinning up pictures of Izzy and Moe on their walls. One bar in upstate New York, knowing Izzy was Jewish, demanded newcomers taste a ham sandwich before being served. None of this perturbed Izzy however. At the upstate bar he accepted the sandwich cheerfully and as he went to eat it, carefully blew the ham out of the sandwich.

Unlike many federal agents, Izzy and Moe were never on the take and thus beholden to no one. But they weren’t always thanked for their incorruptibility. Their superiors in Washington, D.C. resented their popularity. So did their colleagues. The sheer volume of arrests they made— often 20 or 30 bootleggers before breakfast—made other Prohibition agents look bad.

In November 1925 the pair were among 35 Prohibition agents fired by the new Prohibition administrator because they “did not measure up to the standards of efficiency.” Such a claim was clearly bogus. In five years Izzy and Moe arrested some 4,932 sellers of alcohol, accounting for nearly two-thirds of all Prohibition arrests in New York City. Even Eliot Ness fighting Al Capone’s mob in Chicago couldn’t match Izzy and Moe’s success rate.

The “master-minds of federal rum-ferrets” were forced into another career: selling life insurance. Fortunately they were good at that too. Indeed Izzy liked to boast that many of his policies were sold to the very bootleggers he had arrested just a few years before.