The Crime Lords, led by Silvermane, are holding The Kingpin accountable for his failure to eliminate Spider-Man. So six of the Wall-Crawler's greatest enemies are called together to do the job: Doctor Octopus, Mysterio, The Scorpion, The Rhino, The Shocker and The Chameleon. Unfortunately, Spidey's powers have been on the blink due to the changes in his blood chemistry.
