It's mainly about Harry's second son Albus Severus Potter "you were named after two of the greatest wizards I knew and one of them was in Slytherin" so...Albus potter gets sorted into Slytherin and he becomes friends with Scorpius Malfoy (Draco's son) And then there's this girl Delphi (delphini) who says she's Amos Diggory's (Cedric's fathers) niece. So suddenly Amos wants his son back, so he goes to Hermione and Harry (Hermione is the minster for magic) for a time turner that had been found courtesy of a death eater, Harry refuses the existence of the time turner, Albus and Scorpius try to take matters in their own hands, Delphi offers help, they polyjuice into harry ron and Hermione to get the time turner (on the first day of school!) Minerva tells ginny, harry, Draco that their sons never arrived, Harry goes to the centaurs for help, Bane (who was a centaur) says "there is a dark cloud surrounding your son" harry takes that 'dark cloud' to be Scorpius who is rumored to be Voldemort's son. While Delphi, Albus, Scorpius time travel to the quidditch world cup to save Cedric. Everything goes wrong and in the timeline, Hermione is a teacher, Ron married Padma Patil. And in another timeline, Voldemort takes over Albus isn't born (harry's dead) Umbridge is the head of the school, Scorpius is basically a king, but Scorpius tells snape and Hermione about this. all in all they get back safely. They again try to fix things. they ask moaning myrtle (Myrtle Elizabeth Warren) for help. She tries to keep their secret, but Harry was keeping an eye on the marauder's map and he saw them vanish, while in the past, Delphi reveals her true identity to Scorpius and Albus (she's the daughter of Voldemort, trying to bring back voldy) there was a new prophecy “When spares are spared when time is turned when unseen children murder their fathers: then will the Dark Lord return.” (spare is Cedric, unseen children murder their fathers means that in another timeline, Harry was defeated) So, Delphini goes to the Godric's hollow to prevent voldy from killing Harry (hence saving him) but Albus and Scorpius, inscribe a message on baby harry's blanket, The blanket that Harry Potter still had, harry sees it and Hermione, Draco, ron, ginny, harry travel back in time, Harry polyjuices into voldy to fool Delphi, but she was smart and saw right through their plan, Delphi was about to kill Harry when Albus saved him, they return back to the present and continue their lives, now, peacefully