Plaza Studio

A professor who found out a formula to make diamonds from oil is killed in Tehran and his nephew who is a spy is sent to Tehran by Interpol in order to find the formula.

With Rezvan's death his nephew Betty comes to Iran from abroad to sell the lands she has inherited from him. Fahim wants the lands for himself but Bahram is preventing him. This put them to confront each other while Betty too falls in love with Bahram.

Hamid, who has a dispute with his wife "Mehri", leaves his wife and daughter "Mahtab" and goes to a cafe. Hamid meets a dancer named Mina, who tries to trap him in a smuggling gang led by Ahmad.