Laurence Harvey plays a young down-and-out hoodlum, Freddie, who Sydney Taffler (Marcon) employs to help him on a smash and grab raid. But this isn't just any robbery but the theft of a piece of rare ceremonial jewellry in Cambridge associated with a University college.
All goes well until a man stands in the way of them and their getaway car and Freddie shoots the man who falls into the getaway car. Freddie and Marcon flee pursued by a gang of college students and take refuge in a college garden. Meanwhile the getaway driver Sam (Harry Fowler) dumps the car ensuring that the body, and the man's identity, isn't discovered until much later in the day.
Marcon and Freddie pose as two college visitors and befriend Josephine (Kathleen Byron), the daughter of a professor, while they plan their escape. Eventually they are caught when it is revealed that their victim's identity is the college professor and the missing jewellry is discovered.
