The Creature Below (2016)

The marine biologist Olive Crown applies to the research of Dr. Fletcher in deep waters and is hired. However Olive is attacked by a huge creature that damages her underwater equipment and she has amnesia with the trauma. Dr. Fletcher fires Olive and she finds an egg in the equipment and she brings it home. She leaves the egg in the basement of her house, and soon the egg hatches and Olive captures the offspring to study. She tries every type of fish to feed the creature but none satisfies it. Olive finds that the creature feeds only with her blood. Soon Olive kills people to feed the creature. Meanwhile her boyfriend Matthew "Matt" Gardiner realizes that his girlfriend is changing her behavior, but he does not suspect that she is feeding the creature with blood from her victims. When Olive's sister Ellie Crown comes to her house to spend a couple of days, she finds that something is wrong with Olive and snoops around the basement with tragic consequences.