Xenofon Tsigenis, a naïve man who works as a collector at the plastic company "K. Dervisis & Co.," saves the company's files from a fire. Among them are the accounting books as well as some love letters. The accounting books reveal that one of the two partners, Kosmas, is stealing from the other partner, Telis, while the love letters are from Kosmas's wife, Lela, to Telis. At some point, Xenofon learns from Kosmas's maid, Vaggelio, who is also interested in him, that they are considering firing him. Although he does not fully understand the value of the information in his possession, he resorts to blackmail. Kosmas and his accountant, as well as Telis and Lela, attempt to steal the documents, leading to everyone ending up at the police station, where the truth is revealed. In the end, Xenofon will marry Vaggelio, despite the protests of his landlady.