On Halloween, three-year-old Lily begs her parents to watch her swim. Marcus and Nora are too busy with each other to look. A giant gator drags her under and swallows her leg whole. Marcus dives in, beats the beast bare-handed, rips her leg out of its throat, and races her to the hospital just in time. Weeks later, a second gator surfaces in the same pool — a mother guarding her eggs. This time, will he be watching?