Derek is a Supervisory Special Agent of the FBI's Behavioral Analysis Unit. He specializes in explosives, fixations, and obsessive behaviors. Derek is a suave ladies man, and loves to crack jokes. He's an overeager attention seeker, and constantly quotes regulations and being the only member of the team who understands Reid's "jokes". He's incredibly loyal and a very hard worker. He genuinely wants to catch serial killers and he genuinely cares for everyone on the BAU.