An insurance company is after Maggie to give her money inherited from an uncle, right after Mr. Lucky puts her into hiding when she witnesses a mob killing.
A wartime buddy sends Mr. Lucky a hideous painting for a birthday gift which the artist desperately wants back.
Thieves seem particularly interested in stealing a check a lady gave Mr. Lucky to pay off a large gambling debt.
The Fortuna has to be evacuated when a mine is discovered attached to the ship's anchor. Then it's discovered that the "mine" is actually a repository for gems being smuggled into the U.S., and the smugglers will do anything to get them back... including using a real mine to blow up the Fortuna if Lucky doesn't deliver.moreless
Lucky encounters a missing heiress who has left her sheltered existence to seek out life - beatnik style. She threatens to charge him with kidnapping unless he and Andamo show her the hip scene. They reluctantly agree, but some crooks realize who she is and try to kidnap her for the ransom.moreless
After a woman taunts a businessman at the Fortuna, she promises Lucky that in 24 hours she'll have the $5,000 to pay off her gambling debts. However, when Lucky and Andamo go to get the money, they discover that someone has murdered her.
An ex-convict who can't handle the outside world seeks Mr. Lucky's help in returning to prison.
Lucky is challenged to a high-stakes game of pool by a gambler who brings a pair of thugs with him and promises that if Lucky wins, he dies. Things get complicated when Nick bets a mobster that Lucky will lose, while Andamo tries to hedge the bet by convincing an oil magnate to bet that Lucky will win... and the two men compare notes.moreless
Lucky is on the lookout for counterfeit money when the police inform him that phony bills are being put into circulation from the Fortuna's port.
A friend of Lucky's boards the Fortuna II to hide from the mobster who is pursuing him.
Lucky and Andamo, penniless, crash a costume party aboard an enormous yacht to get some food. Due to a case of mistaken identity, Lucky messes up a conman's scheme and offers to help the man and his attractive daughter Maggie raise the money to pay off his debts to the local mob.moreless
Mr. Lucky and his associate Andamo are forced to abandon their casino in Andamo's island country when the corrupt president learns that their yacht, the Fortuna, has been used by a group of revolutionaries to bring in arms.