At the start of this issue, Spider-Man is attacked by the Man-Wolf, but manages to roll out of the way before it can hurt him. The two then fight, but as they do Spider-Man thinks about how he doesn't really care about fighting the Man-Wolf, as he still misses Gwen Stacy, who died recently. In the middle of the brawl, Spider-Man notices a gemstone around the Man-Wolf's neck, and tries to remember where he's seen it. A minute later, the moon starts setting, and the Man-Wolf runs off. Spider-Man follows the Man-Wolf for a bit, but as he does a slash wound he received from the Man-Wolf earlier takes its toll, and he is too weak to follow any further.
Peter returns to his apartment, where he finds that Harry Osborn is missing. As he bandages his slash wound, Peter tries to remember who he saw wearing the gemstone the Man-Wolf was wearing before, and tries to work out why J. Jonah Jameson would try to protect the Man-Wolf after he attacked him. Peter then passes out.
The next day, J. Jonah Jameson goes to his son's apartment, where his fears are confirmed, as he finds his son wearing the same costume that the Man-Wolf had been. John Jameson wakes up, and tells Jonah about how he became the Man-Wolf. Several months ago, John Jameson had been on a mission for NASA when he found a mysterious rock on the moon. Upon taking it, he had it made into a pendant back on Earth, but when the moonlight touched it, it turned John into the Man-Wolf. John tells Jonah that any hope of a cure is impossible, since the stone grafted itself to his skin, and can't be removed.
A big later, Peter Parker changes to Spider-Man, and goes to the Daily Bugle to ask Robbie Robertson if he knows anything about the gemstone he saw the Man-Wolf wearing. However, after Spider-Man comes through the window, J. Jonah Jameson steps inside with some police, who use tear gas to drive Spider-Man out of the room. Spider-Man then changes back to Peter Parker and goes to visit Mary Jane, but the fight with the Man-Wolf and the police has left him exhausted, and he collapses. Mary Jane then kicks him out, since she's sick of him being so depressed about Gwen Stacy's death.
Meanwhile, John Jameson's fiancee Kristine Saunders arrives at John's apartment, ready for a date. Unfortunately for her, John changes to the Man-Wolf and attacks her as she tries driving away. At the same time, Spider-Man works out that the costume the Man-Wolf was wearing was similar to that used by astronauts, and therefore the Man-Wolf must be John Jameson. Spider-Man then heads to John Jameson's apartment to confront the Man-Wolf.
Upon reaching the apartment, Spider-Man stops the Man-Wolf from attacking Kristine just in time. Spider-Man then tries covering the gemstone with webbing, to cut out the moonbeams that are being transmitted to it, but the Man-Wolf rips it off. After that fails, Spider-Man rips off the gemstone, without realising that it's grafted to John's skin. He then throws it in the river, before leaving J. Jonah Jameson to attend to John.