In this film, Jürgen is Holger, a translator for Italian books, married to the teacher Simone. They have a teenage daughter called Lara and live in a nice area in Koeln (Cologne to you). It starts with a birthday party for Lara, who turns up late with her new boyfriend Janis (they spent some time necking in the garage). Janis goes to the same school as Lara, where Simone is also teaching. He is very charming, starts flirting with the mother a bit but also makes subtle advances to Holger. There are a few more scenes of their family life, showing that Holger is a good husband and very loving father to Lara, that this is as harmonious a family as one can find.
Next day, on the way to his boxing club, Holger by chance discovers that Janis sells himself in the train station and it becomes clear, that at the birthday party Janis noticed right away, what Holger only gradually realizes later: that he is very much interested in boys and this one in particular.
When Holger returns from training, he finds Janis installed in his home in the guestroom for a few days, while his single mother is in hospital. Holger protests but doesn’t tell, why he thinks that Janis is not the right company for his daughter, so Simone thinks, it is just the normal concern of a worried father. She herself is quite charmed by the boy.
One night, Janis takes Lara out to the disco but there Janis is called away by one of his friends from the gay scene and Lara returns home on her own. Holger is very upset, that Janis let his daughter go alone around the city in the middle of the night but he manages to be nice to his daughter, who in turn worries about Janis. He sends her to bed and then goes to the train station, where the whores hang out. He does indeed find Janis and this time, Janis notices that he is being watched and later comes up to Holger’s car asking him, whether he came to this area often.
Back at home, Holger throws Janis out of the house in the middle of the night. At breakfast next morning, the family is very upset about his making this decision without discussing it with anybody but he still doesn’t tell about the real reasons. After some quarelling he is sent after janis to fetch him back.
Holger visits Janis in his mother’s flat, in an old, seedy part of the town. After a first confrontation they start talking: Janis about his "job", he mostly does it for money and always uses comdoms, so Lara is at least safe from HIV, about his mother and her boyfriends and the father he misses. Holger about his earlier life in Italy, when he still dreamed of writing a novel. In the end, Janis returns with Holger under the condition, that he tells Lara about the other side of his life.
Janis doesn’t manage to tell Lara and rather pretends not to like her anymore. At the evening of a school party, everybody except Holger goes. Janis comes home early, bringing some cookies from the party for Holger and makes some very open advances, which Holger very harshly rejects. Instead, later on, Holger makes love to his wife very temperamentally, so that Janis can’t help listening to them.
As a revenge, Janis takes up his affair with Lara again, making sure that Holger will see them. Which he does and promptly makes Janis leave again. He takes him and his luggage to the mother’s flat. On the way, they quarrel in the car and end up having sex. Lara, who followed them on her bike, sees them and gets home in complete shock. She tells her mother, what she has seen.
When Holger comes home, he has a confrontation with his wife, who wants some explanation, which he can’t give. He moves to a hotel, where Janis comes to visit him. A few days later, Holger meets his wife to get his mail and when they get talking, he confesses, that he vaguely knew, he had an interest in boys, but that always his love for her and the family had been infinitely more important to him. It is quite clear, that they still love each other and they decide, that Holger should come back home.
Lara is completely opposed to this. She undermines all attempts to recreate the old family life. In the middle of all this comes a call for help from Janis, who has been beaten up by a customer. Holger can’t refuse this call for help and stays with Janis and starts living together with him. Simone finally visits the two of them to get a clear decision from Holger. He decides to stay with Janis.
Holger soon discovers, that the gay scene is not for him. It is a scene for young men, who change partners frequently, whereas Holger really wants a family life, but this is not possible with Janis.
Almost a year later, at Lara’s next birthday party, Holger creeps back with flowers for his daughter. His wife makes him leave, but this time Lara comes running after him.
There seems to be another chance for a reconciliation but it is too late, Holger can’t get away from his obsession with Janis although he knows, that his family is what he really wants. Janis is now also getting tired of him and even makes him pay for sex.
Simone tries to bribe Janis to go away and leave Holger in peace. Janis just makes some nasty remarks and Simone, who has Lara with her in the car, decides to run over him with the car. In the last moment, Holger pushes Janis aside to save him and gets killed by the car instead.