After an older lady hangs herself in a church, a new psychiatrist discovers she was obsessed with the disappearance of his eight-year-old son, who vanished three years earlier. Meanwhile, three city dwellers are restoring a house when they realize it is haunted.

Based on an astonishing true incident that took place on the frigid seas off Iceland in 1984, The Deep fashions a modern-day everyman myth about the sole survivor of a shipwreck, whose superhuman will to survive made him both an inexplicable scientific phenomenon and a genuine national hero.