Rex (The Eternal Mystery)

Rex was a captain of the palace guard on Krontep who was assigned to the temple of Yrcanos. He caught a hooded figure in the temple and chastised them for being there, before discovering that it was his warrior queen Peri Brown. He told Peri what her disappearance did to the planet and that he wanted to travel the universe like her. She invited him on board the TARDIS. (WC: The Eternal Mystery)