The first book in the Percy Jackson & The Olympians series, The Lightning Thief introduces readers to Percy Jackson, demigod son of Poseidon, and his friends at Camp Half-Blood.
Percy, a sixth grader who's been kicked out of several schools, suffers from dyslexia and ADHD; he's never met his real father; and his mother, whom he adores, is married to a jerk who verbally abuses Percy and his mother. When monsters start coming after Percy and he discovers that his best friend isn't exactly what he seems, his mother helps him escape to Camp Half-Blood in Long Island, where he finds out the missing information about his past and a great deal more. The Greek gods exist, and they have a lot of children populating the earth; Camp Half-Blood is a safe haven for them. Because he is the son Poseidon, of one of the "Big Three" - Zeus, Poseidon and Hades - he is hunted even more than the children of the other gods and goddess. He also learns that someone has stolen Zeus' master lightning bolt and Zeus think it's him.