From Milestone Media, The Big Bang was both a play on words and the event (a large gang fight, or Gang Bang) that helped get their fictional universe started.

All the major street gangs of Dakota came together on Paris Island to decide who was the top dog once and for all. Unfourtunately for the gang members, the police had found out about the Bang an planned to be there with a special radioactive tear gas. This would 'tag' all the partcipants, allowing the police to pick them up over the next few days. What the police didn't know was that this 'tear gas' was actually Quantum Juice, a substance with variable and unpredictable effects. Of the 500 bangers involved, most (along with the police) were killed instantly by the Juice. The few survivors were radically changed, mentally and physically. Many gained superhuman powers. Members or the Paris Bloods and the Force Syndicate merged to become the Blood Syndicate, the supreme gang of Paris Island.