The franchise consists of five films directed by and written by S. N. Swamy :

Oru CBI Diarykurippu w English Subtitles Online : r/MalayalamMovies

The third installment where Iyer investigates a death-row criminal's confession about an unsolved murder.

(1989) : Investigates the mysterious death of a famous actress. Sethurama Iyer CBI (2004) : Iyer reopens a case for a death-row convict. Nerariyan CBI (2005) : A mystery centered around a supposedly haunted mansion. CBI 5: The Brain (2022)