Delong was a descendant of the first human colonist of Carista VII. He often had nightmares. He saved the Eighth Doctor and Lucie Miller from space after the attack from the Wirrn. He told the Doctor about his ancestors sacrificing people to the Wirrn. He helped the Doctor stop the Wirrn from killing all humans on the planet, Carista VII. (AUDIO: Wirrn Dawn)