Agatha Harkness is building a new Darkhold—and she’s pitting Earth's Mightiest Heroes against each other to do it! First on her list is Spider-Man, whose regular day is turned upside down when he involuntarily walks through a portal to a remote, magical city… where he encounters Wolverine! As more of Agatha’s plan is revealed, can even Scarlet Witch and the Avengers put a stop to it?