Doctor Who episode 268: The Ambassadors of Death – Episode 4 (11/4/1970)
The conspiracy begins to unravel as Carrington is spooked by the Doctor’s continual questioning, and Reegan continues to eliminate weak links and loose ends: after last week’s unfortunate henchmen this time it’s the turn of the unlikely-accented Dr Taltalian, who falls victim to a bomb in a briefcase that looks like something Q-Division might have thought up, and of Sir James Quinlan, whose willingness to tell all to the Doctor makes him too dangerous to live.