Sethurama Iyer, the CBI Officer, comes to Kerala once again. But this time he is on vacation, spending his time with his sister and family. He has a visitor there, Fr. Gomez, who comes from Isow Alex, a convict awaiting his execution at the central jail. Upon Fr. gomez's request, Iyer visits Isow Alex, where he confesses that he had done six out of seven murders which was charged on him. He didn't do the last one. Now Iyer has to start the investigation before it is too late for CBI to correct the mistake. He starts investigating the case in his usual style.