Composer John Berger is plagued by marital problems and struggling with a deadline for the music for an operetta. When he is visited by the muse of music, Polyhymnia, the melodies begin to flow, but she also causes a lot of complications in his earthly life. Like John's wife Irene, she falls in love with flight lieutenant Harry, while her father Zeus looks on disapprovingly and decides to intervene. Meanwhile, the premiere of the operetta is fast approaching.
| Actor | Role |
|---|---|
 Bodil KjerMusen Polyhymnia | Musen Polyhymnia |
 Hans KurtJohn Berger | John Berger |
 Poul ReichhardtLøjtnant Harry Smith | Løjtnant Harry Smith |
 Ellen GottschalchRosa Ellias | Rosa Ellias |
 Johannes MeyerZeus | Zeus |
 Ib SchønbergVolmer | Volmer |
 Knud HeglundOvertjener Mortensen | Overtjener Mortensen |
| EEdith HermansenNot listed | Not listed |
 Keld MarkuslundNot listed | Not listed |
 Bjørn SpiroNot listed | Not listed |
 Lis Adelvard Not listed | Not listed |
 Svend BilleTeaterarbejder (uncredited) | Teaterarbejder (uncredited) |
| EEgo Brønnum-JacobsenNot listed | Not listed |
 Anna Henriques-NielsenNot listed | Not listed |
 Thorkil LauritzenNot listed | Not listed |
 Lily BrobergIrene Berger | Irene Berger |
 Per BuckhøjMand i kontroltårn | Mand i kontroltårn |
| JJørn GrauengaardNot listed | Not listed |
 John PriceProfessor Ørnfeldt | Professor Ørnfeldt |