On a tourist trip abroad the passengers on the coach witness an assassination attempt on the President Hurkas. One of the tourists has evidence against the perpetrators, and is killed when the coach reaches Sweden. Another passenger observes how one of the perpetrators is picked up by a yellow car. She is kidnapped and locked up in a mental hospital.
The rich, aristocratic Katarina Hassel have an architect renovate her mansion. Katarina fall in love with the young architect, Gunnar Stenwall. Alas, he doesn't fall in love with her. But perhaps if Gunnar would meet her identical sister, who works in Stockholm as a waitress, he would fall in love with her instead? So Katarina travels to Stockholm to act as her non-existing sister.
In England, a famous jewel collection is stolen. The police suspect that the jewels have been smuggled to Sweden, and in Stockholm, the young insurance detective Peter Holmer is commissioned to trace the stolen jewels. The tracks first lead Peter to a certain ballet master Lando, but when he comes to Lando's flat, he finds him murdered. Before the police were summoned, Peter saw a young lady smearing from the floor. He tries to catch her, but when he gets down the street she disappears in a taxi..
"Two Women" - Cecilia is in hospital after being subjected to an attempt on her life. Her husband is called to the hospital. Cecilia deliriously mentions a mutual friend. The husband seeks out the friend.
Filip Palm works as a clerk. His hobby is creating inventions of different sorts. He has just received a big inheritance and has fallen in love with Gun Svärdsjö.
