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The psychological detective story Passenger No. 23 takes place on the high seas, a place that seems to have been created for the perfect crime. Detective Martin Schwartz's wife and son went on a cruise on a ship and disappeared. Five years later, an unknown woman, a passenger on the same ship, announces that she knows something about his son, who may still be alive. Martin embarks on a journey as an undercover agent and learns that twenty-three people disappear on cruise ships every year. And among them is a little girl who disappeared on the same ship and reappeared. With his son's toy in her hands...

For fans of quality detectives with an unpredictable ending.