Gigolo gambler Steve Wiley (Dean Martin) cheats movie buff Malcolm Smith (Jerry Lewis) when he wins a car in a raffle, claiming that he won it too.
Refusing to give out two cars, the raffle promoter merely tells the men they will have to share the car (much to Steve’s annoyance as he has debts to pay).
Trying to steal the car, Steve tells Malcolm that he lives in Hollywood, next door to Anita Ekberg. When Malcolm hears this, they both set out for Hollywood – along with Malcolm’s Great Dane, Mr Bascomb – and the adventure begins.
Along the way, they meet aspiring showgirl Terry Roberts (Pat Crowley).
Hollywood or Bust was the last film that Dean Martin and Jerry Lewis did together before breaking up as a comedy team. Dean and Jerry did not speak to each other at all off the set during filming.