In Huntleigh prison, a group of cell mates (Peter Sellers, Bernard Cribbins and David Lodge) plan the perfect burglary. By escaping the day before their release, then breaking back in again, they will have the perfect alibi when they rob a maharajah's palace of its diamonds - they will seemingly never have left their cell. Peter Sellers is superb as the charming convict but he leads a delightful ensemble cast of British character actors, including Cribbins and Lionel Jeffries, who would all return with Sellers for the similarly themed The Wrong Arm of the Law three years later.