Ten scientists trapped in a mobile science laboratory at the South Pole realize that one among them is a killer.

A unique story told over two distinct halves, “Summer” follows Sam, a man drawn to a mysterious island off the British coast where he encounters a group of islanders set on preserving their traditions at any cost. “Winter” follows Helen, a strong-willed outsider who comes to the island seeking answers, but whose arrival precipitates a fractious battle to decide its fate.