Before The Maker remade Earth-6160, he left Miles Morales the key to reach his new universe... and when Miles' baby sister, Billie, uses it to travel to the Ultimate Universe, it's up to Spider-Man to save her! But the Ultimate Universe is never safe for any Spider-Man! When the Spot attacks, Miles will have to team up with an all-new Peter Parker — and that's just the start of his journey across Earth-6160.
