Pagal Nilavu (English: The Afternoon Moon ) is a 1985 Tamil film directed by Mani Ratnam, featuring Murali, Revathi and Sathyaraj in the leading roles. It is about a carefree youth caught between his loyalty to a mafia don and his love for a cop's sister. The film's score and soundtrack were composed by Ilaiyaraaja, while the cinematography of the film was handled by Ramachandra Babu. Pagal Nilavu marked Mani Ratnam's entry into Tamil cinema, though the film became a failure at the box office.
Selvam (Murali) is an aimless youth in Muttam, Kanyakumari who, out of a sense of deep gratitude, ends up joining the gang of Devaraj aka Periyavar (Sathyaraj) and the complications which arise when he falls in love with Jyothi (Revathi), the sister of Robert Manohar (Sarat Babu) an honest and committed police inspector who is newly posted to the town. Periyavar pretty much runs the town and though he helps people in need, he is a diabolical kingpin who will not compromise on his hold of the town for anything. He wins Selvam’s undying loyalty when he helps him with money and power at a critical juncture to save his mother.
In this backdrop Robert takes charge and moves into the town with his sister and daughter. Being uncompromising in his morals, Robert is automatically drawn into a game of one-upmanship with Periyavar and his gang. He also consequentially cannot stand Periyavar’s chief henchman Selvam, and is consequentially drawn into continuous verbal and physical duels with him. Selvam meanwhile falls hook line and sinker to Jyothi (Revathi) and tries every trick in the book to woo her and eventually wins.