'Rocks' Owen, the well-off owner of a car-hire business, is found murdered; the last place he was seen alive was the Blue Parrot nightclub. Scotland Yard go in to investigate, with the help of a visiting American detective and a nightclub hostess who may not be all she appears to be.
A young married physician discovers a mermaid, and gives into her request to be taken to see London. Comedy and romantic entanglements ensue soon after.
