Mr. Saadat's [Morteza Ahmadi] daughter Manizheh [Soroor Najatollahi] has agreed to marry Engineer Mehran [Ali Shoa'i]. Mr. Saadat, a mistrustful man, has Mr. Taqi [Akbar Abdi] keep an eye on Mehran. Mr. Taqi claims Mehran is a member of a gang of heroin smugglers. It soon becomes clear the smuggler in question [Babak Shoa'i] is someone else who resembles Mehran and lives in the building where Saadat lives; Mehran and Mr. Saadat's daughter are free to marry.