Nelson DeMille spins an ephemeral mystery out of the real-life crash of TWA Flight 800 in July 1996 in Night Fall. A pair of adulterous lovers film themselves having sex in the Long Island surf and discover that the tape captures more than their private fireworks. The couple vanishes, along with the film, leaving a lens cap and a hotel blanket on the beach to tantalize investigators. Did they keep the tape? Does it prove that a missile (not mechanical failure) brought down the plane? Five years later, John Corey, the wisecracking detective from DeMille's Plum Island, hunts for the couple using enough old-fashioned sleuthing skills to keep this preposterous, overlong novel moving.