The original Sinister Six was brought together by Dr. Octopus in an effort to destroy Spider-Man. However, Spider-Man managed to defeat them all and sent them to prison. Years later, Dr. Octopus recreated the Sinister Six and replaced Kraven with the second Hobgoblin. They tried to destroy Spider-Man, but failed again. Later after Dr. Octopus was killed by Kaine, Mysterio created the Sinister Seven to destroy Kaine, but they were defeated by both Kaine and Spider-Man. Now after all this time a new Sinister Six has been brought together by the Sandman to destroy Spider-Man, and their newest member was Venom. The latest group to go by the Sinister Six are a group of former members and mercenaries brought together to steal a special computer disc that has the public identities of ever hero on the planet.
Sinister Six I:
Doctor Octopus
Electro
Mysterio
The Sandman
The Rhino
The Chameleon