After naval sergeant Pekka Kuusisto runs into his old crush, nurse Leila, she stays on his mind as he embarks on a submarine combat exercise.
Adalbert "Mussu" Koikkalainen inherits 9,000 marks from his uncle. To buy a milk shop, Koikkalainen needs another thousand marks and work experience, so he applies for a job at the department store Sampo, where he is hired as a scapegoat to receive customer complaints. The saleswoman Irja Salo, who is under threat of dismissal, falls in love with the general manager Vaara, whom she thinks is a traveling salesman.
