The whaling vessel Merciful has just made its strangest catch yet: a massive whale containing a still-living man secreted within its stomach lining. Sailor Isaiah Chase is tasked with keeping the enigmatic man alive.

As their relationship grows, a series of accidents, injuries and deaths quickly befall the ship and its crew. Isaiah is plagued by strangely prophetic dreams, even as the crew continues their endless quest for whale oil under the command of an increasingly unhinged captain.

As events spiral further out of control, the mysterious man confesses what Isaiah has begun to suspect: the crew of The Merciful has fallen into a cycle of punishment for their greed and destruction. Isaiah must confront the sea's vengeance made flesh, and choose between this new, strange love and the fate of the ship itself.