The author Viktor Mattson is writing the last words of his new novel, when his landlady enters his room and tells him to pay the rent before 6 o'clock. The impoverished author hopes to get some advance money from his publisher, but instead he is told that his novel is bad, lacking in realism. To earn some money Mattson becomes a door-to-door salesman of the publisher instead. He goes to Nyköping to sell books, but has no success. At the railway station he bumps into a group of salesmen-to-be for the detergent VIM. As they are going for a free lunch, Mattson joins them, pretending to be one of them. He meets the demonstrator Ingrid Bergsjö, who shows the group the advantages of VIM. In the evening he visits her apartment, and they fall in love. But Ingrid's girlfriend Sonja convinces her that Mattson is a conman, who she must reject. Heartbroken Mattson returns to Stockholm and writes a new novel, based on his sad experience.