Passenger 23

Every year, on average 23 people disappear without a trace from cruise ships. No one has ever come back.

Until now.

Five years ago police psychologist Martin Schwartz lost his wife and son. They were holidaying on a cruise ship when they simply vanished, the case written off as a straightforward murder-suicide.

They are not the only parent-and-child pair to have disappeared from the ship in recent years – and yet, the authorities seem unconcerned.

But when a missing girl reappears – carrying Martin's son's beloved teddy bear – the police won't be able to avoid the truth that something sinister is lurking on board...