Pagal Nilavu (The Daytime Moon) is a 1985 Indian Tamil-language gangster film directed by Mani Ratnam, marking his debut in the language.
The story revolves around Selvam, an aimless youth who joins the criminal enterprise led by Devarajan (Periyavar) due to gratitude for saving his mother's life. As complications arise, Selvam falls in love with Jyothi, the sister of Peter, a newly arrived honest police inspector.
The film features Murali as Selvam, Satyaraj as Devarajan/Periyavar, Revathi as Jyotham (Jyothi), and Sarath Babu as Inspector Peter. The score and soundtrack were composed by Ilaiyaraaja, while the cinematography was handled by Ramachandra Babu.
Pagal Nilavu was released on June 28, 1985, and marked Mani Ratnam's entry into Tamil cinema.