Here Comes Trouble

It's a wacky world aboard a cruise ship. Third Engineer Paul Kelly has a fighting courtship with Arline Judge. He's busted to the black gang for helping a drunk passenger get aboard, then promoted when a fellow stoker goes mad and Kelly saves the day. In the meantime, passenger Gregory Ratoff has purchased a valuable ruby, which two pairs of thieves are after. Ratoff knows this, but doesn't mention it to anyone until one set is successful.

It's an inoffensive comedy-mystery, given the sort of gloss that had come to Fox after it merged with Zanuck's 20th Century Production. Given the cast and producer (John Stone), as well as the release date, I believe this B movie was a leftover from before the merger.