The War Games
S6, E36: Finding evidence of alien technology in Smythe's office, the Doctor, Jamie and Zoe make their escape in Lady Jennifer's ambulance, but Smythe gives orders to have them killed.

S6, E36: Finding evidence of alien technology in Smythe's office, the Doctor, Jamie and Zoe make their escape in Lady Jennifer's ambulance, but Smythe gives orders to have them killed.