குணா

Kamal Haasan

— Gunaa

Roshini

— Rohini

Rekha

— Rosy

Janagaraj

— Gunaa's uncle

S. P. Balasubramaniam

— CBI officer Ramaiah

Girish Karnad

— Doctor Ganesh

Sharat Saxena

— Suresh Kumar

Pradeep Shakti

— Ismail

Ananthu

— Gunaa's cellmate

Sethu Vinayagam

— Doctor

Ajay Rathnam

— Inspector Moovendar

S. Varalakshmi

— Manonmani

Kaaka Radhakrishnan

— Madasami

Saritha

— Rohini (voice)

R.S. Shivaji

— Barber (uncredited)