Damon Foster was considered the agent of agents. He worked for the FBI and was known for catching any and all serial killers that he investigated.
He assisted Marc Simmons research The Crocodile Killer. He steered Marc towards Travis Quinn, the real killer. Foster's plan was to catch Suture, who was also serial killer. If the Crocodile Killer moved to kill his 23rd victim, he knew Suture would show up who always stops serial killers on their 23rd victim. He had fallen in love with Suture and her work over the years.
He blackmailed Simmons to assist him and told him he'd reveal the true killer of his kids and wife if he helped him. Simmons desperate to find his family's murderer agreed. Suture appeared and Foster was critically injured by the Crocodile Killer in the struggle.