Terry's the strong silent type. He's used to keep his emotions in check, which is necessary when diving into black water with nil visibility, identifying objects with touch alone, like bodies, weapons, etc.
He's a working class boy, and has a seething resentment towards anyone who has had it easy. That's the reason why he's giving Fiona Cassidy such a hard time at first.
He's also a member of the State Protection Group.
Terry leaves the show after an unpleasant encounter with Gina Downie, a young woman who's obsessed with Terry.

Season 1 (1996) - season 2 (1997)
(Last appearance in episode 35,
"Sex Games".)

Season 3 (1998)
Guest appearances in
episode 58 (64) "Bloody Kids" and
episode 66 (65) "Soft Target".