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Book 1: Passenger on the 6:20 Train

Every morning at 6:20 Travis Devine boards a commuter train and heads to work. Devin is a combat officer who unexpectedly left the service and is languishing in a desk job he hates. But one day, everything changes. His ex-girlfriend Sarah has apparently committed suicide. However, Travis has doubts that it was suicide. He has to find out what really happened, because the mysterious murders continue...

So what is behind them? Passenger No. 23

The psychological detective story Passenger No. 23 takes place on the high seas, a place that seems to be created for the perfect crime. The wife and son of detective Martin Schwartz went on a cruise on a liner 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 his hands...

For fans of quality detective stories with an unpredictable ending.