The Sinister Six are a group of supervillain in the Marvel Comics universe, who serve as a collection of Spider-Man's foes. The original incarnation of the Sinister Six was organized by Doctor Octopus and appeared in The Amazing Spider-Man Annual #1 (1964).
After suffering three defeats in a row from the wall crawler, Doctor Octopus realized he required assistance from others in order to defeat Spider-Man. After his recent defeat followed by the police successfully removing the tentacle pack, Doctor Octopus mentally controls his tentacles to come to him and he escapes from jail. Afterwards, he contacted every known supervillain that had crossed paths with Spider-Man, but only five responded: the Vulture, the electrifying Electro, Kraven the Hunter, master illusionist Mysterio, and the Sandman. He also tried to get Doctor Doom, Green Goblin, and Lizard to join him, but Doctor Doom was busy with the Fantastic Four, Green Goblin has his own plans for Spider-Man, and Lizard's alter ego of Dr. Curt Connors had no vendetta against Spider-Man. Knowing he'd never be able to keep the team together for long, Doctor Octopus quickly formulated a battle plan in which each individual member of the Sinister Six would battle Spider-Man in a carefully chosen location, giving each of them personal glory and Spider-Man an early death.
Spider-Man himself had his own problems, as he had somehow lost his powers and prepared to return to normal life as a teenager. While blaming himself for the death of his Uncle Ben, Spider-Man lost his balance and fell down the side of a building, ending up clinging to a flagpole. As Peter returned to his normal life as a student and a freelance photographer, he was unaware of the fact that the Sinister Six realized the Daily Bugle secretary Betty Brant played a large role in Spider-Man's life and kidnapped her, along with an innocent bystander who turned out to be Aunt May. It was then left to the Vulture to spill the beans to J. Jonah Jameson, warning him to inform Spider-Man that Betty was being held hostage along with Aunt May and if he wanted to see them alive, he'd have to battle the Sinister Six.
Despite not having his powers, Peter put on his Spider-Man costume and went to fight Electro at an electrical plant. During the battle, Peter somehow regained his superpowers (the loss was speculated to be caused by his own self-loathing for the loss of his uncle, which he got over when facing a life-or-death situation) and easily defeated Electro. Spidey then battled against Kraven (who confronted him with some wildcat) and defeated this foe too. After defeating Mysterio, Sandman, who he defeated by trapping in an airtight box, and the Vulture, Spidey went up against Doc Ock, who lured him into an enormous fishbowl so he could kill him like a real octopus. The two foes battled and Spider-Man was victorious.
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