Maxim Alexandrovitch Felnikov

 was a Soviet military officer and the observer at a medical facility in 1967. He was researching the Ice Warrior armour and ordered its continuation. He stopped the Seventh Doctor and Ace from getting arrested. He listened to western records. He knew of the plan against the party. He told the Doctor about the Russian experiments with Ice Warrior technology. (AUDIO: Thin Ice)

In 1989, Ace met him in Kafiristan when Nikitin took her there. He and Ace met the Metatraxi and explored what it had done to its men. He thought that he could get Sayf Udeen to give him the demon's weapon. (AUDIO: Crime of the Century)