Double-T

Double-T is a character in Deus Ex: Human Revolution. He is a member of Motor City Bangers gang, involved in the Cloak & Daggers sidequest.

Background
He is a murder witness that Jenny Alexander wants to testify against a crooked cop, Jack O'Malley. Being a gang member however, it is obvious that he wouldn't cooperate, and Adam Jensen is sent to "prep him", as Jenny puts it, which involves knocking out Double-T and his fellow gang members, then leaving them for Jenny's accomplice to "accidentally" stumble upon and take them into custody.

While investigating and meeting O'Malley, it is revealed that he plans to hire a hitman to kill Double-T, and then place the murder weapon in a stash belonging to Derelict Row Ballers, effectively starting a gang war and getting rid of a problematic witness in one stroke.