Leviathan

Bracken, a down on his luck oil man is offered a chance of redemption when a billionaire offers him a job to repair a ghost oil rig in the South Pacific Ocean. The payment is enough to retire him and his small crew. But when they arrive on ghost rig Sera, Bracken soon discovers they're not alone. Something very large circles under the water around the rig. Something that shouldn't exist, but does. A thing of nightmares. And it's hungry...