UNIT soldier (The Ambassadors of Death)

A UNIT soldier was part of the UNIT security detachment to the British Space Centre. He served as a guard at the complex's main gate. He was attacked by one of the radioactive aliens who was trying to break into the British Space Centre at the time. Miraculously, he survived the normally fatal effects of the aliens' blasts and was later seen to be back on duty. (DW: The Ambassadors of Death)

Behind the Scenes
The UNIT soldier was played by Max Faulkner, who later played Corporal Adams in The Android Invasion. It is possible that these two characters are one and the same.