Harris, his mother and his wife are a kooky trio. Enter the forceful inspector from Scotland Yard with his constable – which is strange, notes the wife, for she had ordered an ambulance. The officers proceed to place the three under arrest. It is not clear why; something about a parked car, a bunch of .22-calibre shells in the waste basket, and a robbery of the box office of a minstrel show. But Harris has an explanation: he had parked near an art gallery to let his mother see some paintings by Magritte in which her obsessional instrument, the tuba, figured grandly. But then it develops that there was no minstrel show at all, and the plot goes haywire.