Old man (1001 Nights)

Old Man was the man in the next cell to the Fifth Doctor. He told him that the chamber was the best in the castle, but he thought he was the Sultan. The Doctor thought that there was something influencing him to change his perception, possibly due to the Gantha. He thought that he was in a tower. The Doctor convinced him to leave his rooms. It was due to the Sultan's influence that he lost his memory as he was in fact the Sultan. Because of this he wanted to help the Doctor defeat him. (AUDIO: 1001 Nights)