Novelist J.B. Blackwood is on a cruise with her husband, Patrick, to celebrate their wedding anniversary.

Her former professor, Patrick is much older than J.B. But when they met, he seemed somehow ageless, as all new gods appear in the eyes of those who worship them. He is a film director. A cult figure. But now his success is starting to wane and J.B. is on the cusp of winning a major literary prize. Her art has been forever overseen by him, now it may overshadow his.

For days they sail in the sun. They lie about drinking, reading, sleeping, having sex. There is nothing but dark water all around them.

Then a storm hits and Patrick falls off the ship. J.B. is left alone, as the search for what happened to Patrick - and the truth about their marriage - begins.