V4 was a Voc sandminer robot on board Storm Mine 4. It came under the control of Taren Capel as part of his "robot revolution". SV7 commanded V4 to kill the Fourth Doctor. While it was choking the Time Lord, Kiy Uvanov thrust a laserson probe into its head. This caused extensive damage to its sensors. It pursued the Doctor, who was able to fool it in its weakened state by putting his hat and scarf onto V5, leading V4 to attack its fellow robot, believing it to be the Doctor. It then entered a dormant state. After inspecting the damage done, SV7 decided that Taren Capel's expertise would be required to repair V4. (TV: The Robots of Death)
