On a Mississippi River riverboat that doubles as a casino, Johnny Elvis Presley is a compulsive gambler who has fallen into heavy debt, chasing luck rather than security. His partner in performance, Frankie Donna Douglas, is his girlfriend and a gifted singer who keeps the show lively, even as trouble looms. Alongside them, Cully Harry Morgan is a steady musician and composer whose tunes buoy the act and spark the crew’s morale. When the trio visits a gypsy camp, a tea-leaf reading promises Johnny that a red-haired woman will soon bring him luck, a forecast that sets off a storm of ambition and desire.
Back on the boat, Johnny and Cully cross paths with Nellie Bly Nancy Kovack, Clint Braden’s on-again, off-again girlfriend, whose striking red hair seems to confirm the gypsy’s omen in the gambler’s eyes. Nellie’s presence stirs jealousy in both Frankie and Braden, especially when Johnny gleefully lets Nellie touch his gambling chips for luck after a win, reinforcing Johnny’s belief in the prophecy. The tension among them bubbles over as Frankie watches Braden flirt with another singer, Mitzi Sue Ane Langdon, and the two women become entangled in a web of ambition, romance, and ambition turning into danger. The moment of danger comes when Frankie, overwhelmed by jealousy, fires a shot at Johnny during a performance of Cully’s new song on the ship’s stage, a shocking reminder that the stakes extend far beyond the casino floor.
A Broadway talent scout spots the riverboat's act and buys the rights to Johnny’s song, proposing a move to New York City for Frankie and Johnny to pursue bigger dreams. The boat lands in New Orleans, and the crew and performers descend into a masked ball, where the ladies—Frankie, Nellie, and Mitzi—share a Madame Pompadour costume and mingle with the crowd. The masquerade becomes a stage for a daring ruse: Frankie and Nellie switch places to test Johnny’s belief that the red-haired partner will bring him more luck. When Johnny wins an astonishing $10,000 at roulette, he flings himself into a kiss with the woman he assumes is Nellie, only to discover the switch has occurred, and Frankie’s temper boils over.
Meanwhile, Blackie [Robert Strauss], a dim-witted stooge who works for Braden, hears his boss lament losing Nellie and hatches a reckless plan. He swaps the blank cartridge in Frankie’s stage gun for a real bullet, turning a moment of showmanship into real danger. Braden races to avert catastrophe, but arrives too late on stage, and Johnny is shot for real. Frankie’s heart aches as she forgives his gambling, believing love itself is dying. Yet the supposed fatal wound isn’t fatal after all: the bullet has struck a lucky medallion Johnny wears—one he received from Frankie—which absorbs the impact and leaves him standing, stunned but alive. In the tense aftermath, the couple confronts their intertwined fates—luck, love, and the risky glamour of show business—knowing that fortune can falter in an instant, yet sometimes resilience and a lucky charm can save a life.
