There's a famous story that Chico Marx of the Marx Brothers had a heart attack (not onstage) while he was performing in a Vegas showroom and his engagement was canceled before it was over. And the story is that the heart attack never happened and that was just an excuse to explain the cancellation. The real reason was that he was losing too much money gambling while he was in town. Do you think this is true and are there any other stories about Chico or his brothers playing Vegas?
This is one of those Las Vegas stories where the broad outline is true, but the details get murky.
Chico Marx was unquestionably a compulsive gambler. Even sympathetic biographers describe gambling as the defining financial problem of his life. He reportedly lost millions of dollars over the years on cards, horses, sports betting, and casino gambling, and his brothers repeatedly bailed him out.
As for the Las Vegas heart attack story, you're right that the account of Chico suffering a heart attack while working Las Vegas has been circulating for nearly 70 years. A competing version posits that the "heart attack" was exaggerated or outright fabricated to get him out of a contract. Groucho and Harpo reportedly rushed to Las Vegas after seeing headlines that Chico had suffered a heart attack there, only to discover that he'd faked it to escape an engagement. (Chico put on a musical-comedy variety show that combined his classic vaudeville slapstick, his famous exaggerated Italian stage persona, and his signature virtuoso piano playing. He and Harpo did a residency at the Riviera in the late '50s.)
We couldn't find much evidence that the cancellation was specifically because Chico was losing too much money gambling in the casino and needed an excuse to leave town. Given Chico's reputation, that explanation sounds plausible enough that it has attached itself to the story over the years, but the "fake heart attack to get out of a contract" version appears to be better documented than the "he was getting crushed at the tables" version.
As for other Marx Brothers Vegas stories, here are a few we unearthed.
Chico was a casino's dream customer. He was exactly the kind of gambler they wanted: wealthy, action-oriented, and convinced he could beat long odds. Friends said he would bet on almost anything. If a game wasn't available, he reportedly made proposition bets with strangers over trivial events.
One reason Chico kept performing long after his greatest fame had passed was out of financial necessity. Groucho and Harpo repeatedly stepped in to rescue him from gambling losses. Several Marx historians have suggested that much of the brothers' later work was driven by Chico's need for money.
And here's how serious Chico's habit was. Apparently, a check Chico had written turned up among the possessions of Bugsy Siegel after Siegel's murder. It's said that Chico had to answer questions from the police about it. The check, according to Chico, had bounced, because he hadn't expected it to be cashed immediately — a typical Chico explanation, even to a stone-cold killer like Bugsy.
Harpo was also a gambler, but not anywhere near as compulsive as Chico.
Groucho wasn't nearly the gambler Chico or Harpo was, but he loved Las Vegas and became a popular headliner there in later years. His sharp improvisational style worked beautifully in showroom settings, and unlike Chico, he generally left the casinos with his bankroll intact.
One thing that's striking when you read Marx Brothers history is that Chico was viewed as simultaneously irresponsible and utterly lovable. People who knew him were exasperated by his gambling, yet almost everyone seems to have adored him. Even after decades of losses, loans, and rescues, Groucho and Harpo kept helping him. When you read their letters and interviews, you find plenty of complaints about Chico's gambling, but very little bitterness. They seemed to regard it as an incurable part of who he was.