A young woman, Megan, washes ashore from her blood-stained rowing boat after a treacherous Transatlantic rowing attempt ends in disaster. Suffering from severe memory loss, and with the rest of her crew missing, it falls to a local DCI to uncover what really happened on board the doomed vessel.

As the only witness, Megan attempts to recollect the traumatic events leading up to the shipwreck and prove her innocence. However, the truth is never simple. Memories emerge that point suspicion towards a mysterious crew member who harbours a dark secret, but other clues indicate that the boat was being deliberately sabotaged. The story that comes together is one of a battle against sleep deprivation, paranoia, and distrust, all the while facing a fight for survival against the forces of the ocean.