Two families take a cruise - husband, wife, and two young children in each. The wives are cousins and they are all a tight knit group. They meet another couple also with two kids and go on a zip lining shore excursion. Car breaks down, they find a beach instead, the moms fall asleep while the children are playing in the water and get taken away by a tide. The kids are missing and the hunt is on to find them. Meanwhile the kids come ashore, find a body, get kidnapped, escape, are in a car chase, hop on a train, etc, etc. You see the kids story and the parents, mostly the moms, stories. Very well written, well paced action and suspense. The story was good but the characters were good also. Author really explored the emotions parents would be feeling with their kids missing in a foreign country. These were believable characters, real and with flaws but essentially good people. I'll read this author again.