Ship of Chance

After earning a half-million-dollar reward for helping to capture a serial killer, Greg Paris treats his family to a cruise on the Queen of Hearts, billed as the largest gambling ship in the world. Accompanied by his wife, Dianne; their six-year-old daughter, Jody; Greg's brother, Steve; and Steve's new bride, Inez, they set sail for Caribbean and Mediterranean ports.
But they quickly find out it's not going to be the idyllic vacation they envisioned. Greg and Steve hear rumors of a murder and other disappearances that have occurred on this same ship on different cruises. Soon, they experience the violence firsthand. Inez disappears, and Dianne suffers a vicious assault. It's evident there is a serious criminal element aboard the Queen of Hearts.
Greg, an elementary school teacher in New York City and a former marine who served in Afghanistan, intends to track down Inez's whereabouts on the ship, find the perpetrators, and bring them to justice.