Jack Fisk was formerly the Assistant District Attorney for Jolt City. Allied with the "untouchable" drug lord Samson Snapp, he often sabatoged the efforts of Lt. Dani Handler and the second Green Knight to bring Snapp to justice. When the investigation turned towards finding Snapp's rat on the inside, Fisk arranged for the (thankfully bungled) murders of Handler and Dr. Fay, which he intended to pin on Martin Rock (whom he did not know was secretly the Green Knight). He then had Rock remanded to custody in Earbox Prison, where he assumed Rock would be murdered.
Fisk conspired with Snapp and the hordes of Apelantis to overthrow the United States government. Though the invasion was thwarted and Snapp was arrested for treason, Fisk managed to cover his tracks and evade capture. This led to the Green Knight reminding him that though it took a long time, he hadn't given up until Snapp was brought to justice, implying that a similar dogged pursuit would follow Fisk.
Fisk, admitting nothing, shortly thereafter stepped down from his position as ADA; he was replaced by Tad Dmowski. Fisk's current whereabouts are unknown.
A Special Message from TomEdit
I swear to God, I did not realize until now (2010!) that I named this weasely villain after one of my favourite set designers, who by all accounts is a darling of a man. Just as I didn't realize until much later that Danielle Handler sounds an awful lot like the author Daniel Handler.
I am totally embarassed by this.