|Members:|| Crossbones/Lizard (formerly)|
Kraven the Hunter
Scarlet Spider (formerly)
Ultimate Green Goblin (formerly)
The Sinister Six are a team of six supervillains formed by Doctor Octopus to eliminate Spider-Man. The team was temporarily renamed the Sinister Seven when Ock reformed the team with Scarlet Spider as its secret seventh member.
The Sinister Six's formation is only briefly shown but each villain has had their own battle with Spider-Man prior to joining. Eventually, Doctor Octopus abducted Curt Connors in the plans of using him as the Lizard. The captive sent a message to Spider-Man, telling him to head to Doctor Octopus' underwater lab. Arriving, the web-slinger is attacked by the five members where the mad scientist dubs them the Sinister Six. Spider-Man corrects him that there are only five members but the villain activates a device that forces Connors to transform into the Lizard.
Spider-Man battles the six in the Underwater lab until he tries to separate them. He focuses his motives on the Lizard and succeeds in getting him to revert to Connors, but Doctor Octopus forces him to transform again. Eventually, the six prove too much for the hero to handle and is knocked unconscious. Instead of killing him, the villains agree to unmask him but the Lizard stops them turning into a struggle between the five members. Spider-Man then tricks the Rhino into flooding the lab and flees to the city of Manhattan.
The Six regroup and attack Spider-Man throughout a construction site until the web-slinger flees via a news helicopter, which he uses to contact his team. Arriving at the rendezvous point, Spider-Man is attacked by the Sinister Six who attempt to unmask him once more, but Nova arrives to stop them. Each team member fights against one of Spider-Man's team while Doctor Octopus watches taunting Spider-Man. The hero realizes that the team was formed to combat his own and orders them to switch villains which ultimately leads to their defeat. The Lizard turns on them and helps Spider-Man defeat Doctor Octopus. He then flees into the sewers while Spider-Man follows trying to change him back into Connors. The Lizard manages to escape Spider-Man much to the hero's guilt.
Later, Nick Fury tells Spider-Man he managed to imprisoned the five villains and that they'll locate the Lizard soon enough.