The story opens with the conspicuous celebration of a normally secretive wizarding world; for many years, it has been terrorised by the evil wizard, Lord Voldemort. On the previous night, October 31, Voldemort discovered the Potter family's hidden refuge, killing Lily and James Potter. However, when he attempted to murder their toddler son, Harry, the Avada Kedavra killing curse he cast rebounded upon him. Voldemort's body was destroyed, but his spirit survived: he is neither dead nor alive. Meanwhile, the orphaned Harry is left with a distinctive lightning bolt-shaped scar on his forehead, the only physical sign of Voldemort's curse. Harry is the only known survivor of the curse, and Voldemort's mysterious defeat causes the wizarding community to dub Harry "The Boy Who Lived". Harry (and the Dursleys) are protected by the enchantment that was produced when Harry's mother died while protecting him from Voldemort. This protection will last until his 17th birthday.

On November 1, Hagrid, a 'half-giant', delivers Harry to his only living relatives, the cruel and magic-phobic Dursleys, comprised of Uncle Vernon, a bad-tempered uncle; Aunt Petunia, a woman who appears to absolutely loathe Harry; and Dudley, their spoiled and overweight son. The Dursleys are, in the words of Professor McGonagall, "the worst sort of Muggles imaginable" and seek to deny Harry his magical birthright by making up a false story about Harry's parents dying in a car accident. They treat Harry like a slave and force him to live in a small, cramped closet under the stairs at their Privet Drive home.

However, as his eleventh birthday approaches, Harry has his first contact with the magical world when he begins receiving letters from Hogwarts School of Witchcraft and Wizardry, which are delivered by owls. Unfortunately, his uncle confiscates the letters before he can read them. Much to the Dursley's chagrin, Hogwarts is aware that Harry is not receiving his letters. However, the letters keep on coming and Uncle Vernon decides to move the family (Harry included) to a deserted island off the coast, hoping that the letters will cease. At the stroke of midnight on Harry's eleventh birthday, Rubeus Hagrid (Hogwarts half-giant gamekeeper) kicks in the door of the house where they are staying, and presents Harry with a letter explaining that he is a wizard and has been selected to attend Hogwarts School of Witchcraft and Wizardry. Each book chronicles one year in Harry's life, which is mostly spent at Hogwarts. There he learns to use magic and brew potions. Harry also learns to overcome many magical, social, and emotional hurdles as he struggles through his adolescence, Voldemort's second rise to power, and the Ministry of Magic's corruption and incompetent negligence. After facing many obstacles, forging lasting friendships, and losing countless loved ones, Harry Potter confronts the Dark Lord for the last time, and only one will survive.

For a detailed synopsis of the novels, see the relevant article for each book.