Linus Baker's life takes an extraordinary turn as he is given a classified assignment by the Department in Charge of Magical Youth. He must evaluate an orphanage on a remote island, where six children with magical abilities—one of them being the Antichrist—reside. The island harbors its secrets, with the children's enigmatic guardian, Arthur Parnassus, dedicated to their safety, even if it means hiding from the world outside. As Linus grows closer to Arthur and the children, he's faced with a heart-wrenching dilemma: performing his duty or embracing the family he never expected to find.