Seth is a new social worker. Although the kids and Tracy believe he is part of a gang when he first arrives he turns out to be a nice guy. Toby thinks that Seth is the robber who dropped the money but turns out it is not him.
He is Toby's social worker and gets on well with him. Seth falls in love with Tracy and asks her to come on the road with him and his band as he has decided to give up social work as he doesn't think its for him. Tracy kisses him but refuses. Seth made a appearance after Tracy had phoned him, but he said that he had met someone on tour, so he came back to apologise and they kissed.
He still sometimes sees Tracy, reappearing in the third episode of the third series to take her to the cinema. They couldn't because of a terrible storm. He was beaten by Tracy, Liam and Elektra because they thought he was an escaped prisoner.