Gabriel Sneed was an undertaker in Victorian Cardiff. He believed that his house might be haunted, since the corpses refused to stay dead. He and Gwyenth went to London to find Mrs. Peace, whose corpse has been possessed by a Gelth. They retrieved her and captured Rose Tyler. The Doctor and Charles Dickens followed and they soon learned what was going on. Sneed and the others performed a seance and learned the ghosts were the Gelth. In the undetaker's basement, Sneed was killed and possessed by the Gelth. (DW: The Unquiet Dead)
Behind the Scenes
The part of Sneed was originally written for David Tennant. (REF: Doctor Who: The Inside Story)