Sergeant (Spearhead from Space)

In the 1970s, Brigadier Lethbridge-Stewart and Captain Munro left a sergeant in charge of UNIT's tent in Oxley Woods while his superiors dashed to Brook Cottage to secure a Nestene sphere which Sam Seeley had hidden there. Chief among the sergeant's responsibilities was ensuring the safety of civilian John Ransome.

The sergeant posted a guard in front of the tent, but left the back of the tent unwatched. An Auton entered, killed Ransome, and obliterated the body, leaving no trace. (TV: Spearhead from Space)