Jonathan Bordas, a British bookseller at the end of his rope, plans to commit suicide - but, as he swims out into the Atlantic off the Portuguese coast, far beyond the coastal current and the point of no return, when he is in the last throes of exhaustion and only instinct remains, a rubber raft floats by, Bordas scrambles on board, loses consciousness, and wakes to find seven-year-old Bonnie, another drifter from the Poruguese coast, also on the raft. As they are swept further and further from the coast, Bonnie depending on Bordas for her life, Bordas finding in Bonnie a reason to live, a relationship develops strong enough to sustain them as they find first a life boat, then an abandoned yacht. Together they experience the gifts and depredations of the impersonal ocean, but more important than these forces are the human feelings which develop.