He negotiated an agreement with a Nimon that would give his people the ability to conquer the galaxy. Soldeed was utterly devoted to the Nimon. He believed wholeheartedly that it would fulfil its part of the agreement and would chastise anyone who questioned it. The Nimon trusted only him to enter its presence; anyone else would have been executed. Blaming the Doctor and Romana for interfering, Soldeed tried to kill them both and reverse everything the Doctor had done to prevent the Nimons from coming through their black hole. He was shot dead by Seth. (TV: The Horns of Nimon)