Three students decide to share a flat, each courting a young woman. While they pass the time teasing their rival Piet Janssen (de Klit) and nosy neighbour Mr. Smallebroek, rumours and arguments threaten to drive the boys and their crushes apart.
After serving in the Royal Navy, Manus, Toon and Dries return to Amsterdam working-class quarter 'the Jordaan'. Back home, they find out things have changed while they were gone; Manus's girl Jans has been unfaithful to him, Toon's father now rejects him on account of his dissolute life and barmaid Auntie Piet has been cooking up a scheme to ruin Dries' relationship with his girl Greet.
Comedy of errors centred around a piano and the baby of a servant girl whose existence is unknown to all, based on the play 'A house full of strife' by A. Duprez and A. Milo Bennet.
