Sasha and Carl are drifting apart in more ways than one. When the deluded Carl decides to surprise her with a romantic cruise around the coastline, they could not foresee the horror that will find them in the water. Sasha doesn't feel inspired when she sees the old sloop Carl has been working on with its cracked paint and aging deck. Carl assures her everything is fine and convinces her to get on board for the short 3 day trip. Her intuition tells her no, but Carl's charm and desperate need to pull their relationship back, moves her to make the worst decision of her life.
After the boat sinks, they're forced into a life raft. 12 days later. No one found them. They're alone on abnormally calm waters; no wind, drifting aimlessly and slowly dying from thirst and starvation. The tinned water is sparse, they barely have enough between them to keep alive. Then… Carl eats something he shouldn't have. Sasha spends the next 39 days in terror on an unusual sea fighting starvation, the surreal environment, impending madness, suicidal tendencies and the creature her boyfriend is turning into.