John Ingram and his wife Rae, who’s recovering from an auto accident, are on their sailboat, becalmed somewhere in the Pacific Ocean. Their leisurely isolation is interrupted by Hughie, the lone survivor of a sinking black schooner they spot one morning. Hughie’s story doesn’t quite gibe, so John boards the schooner to investigate, where he discovers the real truth. When Hughie wakes and realizes where John is, he takes control of the Ingram yacht from Rae, and motors off towards the horizon. Can Rae regain control of the boat and find John before the schooner sinks?