Norman Osborn hires Spencer Smythe to design a machine capable of destroying Spider-Man - the Black Widow Spider Slayer. But when Flash Thompson puts on a Spider-Man costume as a party gag, the deadly machine spots him, and he's carried off in Peter's place.

Peter Parker and his college science professor Dr. Curt Conners explore neogenics as a method of limb regeneration. But while experimenting on himself, Connors accidentally becomes the Lizard, a half-man, half-reptile monstrosity that terrorizes Manhattan and subsequently kidnaps his own wife. Spider-Man's task is doubly difficult because he doesn't want to hurt the good friend he knows is trapped inside...but he must stop the inhuman beast who is out of control.