Hardback by an American writer, possibly a female. Has an SF plot but was marketed as a 'young adult with problem' story. YA audience, may have a one-word title. Teenage boy disappears after a UFO sighting (possibly near a lake). After some missing time (days, I think) he is returned to Earth, unharmed & with no memory of what happened. The boy never remembers what happened aboard the UFO; the entire story describes the aftermath of his experience, how he deals with the problems fame brings him.