Hisss (2010)

In Natchi, a small town in the Indian state of Kerala, George States has last stage brain cancer and only six months to live. To prevent death and gain immortality, he decides to extract the nagmani, immortal blood from a nagin, a shape-shifting cobra that can change into a human. He and hired henchmen capture the nag (the male snake) so that the nagin (the female) comes after the capturer to free her mate, thus allowing him to obtain the nagmani by force. He keeps the nag in a glass box where he electrocutes and tortures him. His plan works and the nagin starts following them.

The nagin transforms into a beautiful woman and is later helped by police inspector Vikram Gupta and his wife Maya, who is infertile, causing a strain in their relationship. The nagin helps a few women: one who is beaten mercilessly by her husband; one being raped by a man, and so on. She even protects herself when two men try to rape her. She turns into a giant cobra and brutally kills those two men, some of George's henchmen who were involved in the capture of her mate as well as men who torture women. She turns back into a human after her killings. Inspector Gupta tries to help the nagin find her mate but at the same time, tries to investigate the murders, unaware she is responsible for them. Finally, Nagin reaches George's hideout where she reclaims her mate and they have sex, leading her to become pregnant. George attempts to capture the nagin during intercourse since this is when she will be most vulnerable.

Wearing a suit that hides his heat signature, Gerge lures the nagin by using her dying mate as bait for a trap. He captures her and tries taking the nagmani but at that moment, Inspector Gupta arrives and helps her. Angered by the death of her mate at the hands of George, the nagin turns into a half snake, half human hybrid and throws him in the glass box where her mate was kept and electrocutes him to death. She leaves the hideout, carrying her dead mate. Inspector Gupta is amazed at everything he has just witnessed. He returns to his wife Maya, who later gives birth to their baby, while the nagin, back in the form of a beautiful woman, watches over the nest of eggs she has laid, which hatch into numerous baby cobras.