Lieutenant Rip Crandall is hoodwinked into taking command of the "Wackiest Ship in the Navy" – a real garbage scow with a crew of misfits who don't know a jib from a jigger. What none of them knows, including Crandall, is that this ship has a very important top-secret mission to complete in waters patrolled by the Japanese fleet. Their mission will save hundreds of allied lives – if only they can get there in one piece.
Rick Mason is the no-good lowdown rat who tries to capitalize on postwar patriotism and grief. He finagles a war widow into giving up her savings for a nonexistent memorial. When Mason falls in love with the widow he has pangs of conscience, but he reckons without his con-artist boss, who tends to bolster his arguments with muscle and bullets.
Ma and Pa do their bit to hook lumberman Brad Johnson up with spoiled socialite Sally Flemming. Ma teaches Sally how to behave like a hick so she'll be compatible with Brad.
