The Twin Dilemma is the seventh and final serial of the 21st season of the British science fiction television series Doctor Who, which was first broadcast in four twice-weekly parts from 22 to 30 March 1984. It was directed by Peter Moffatt and written by Anthony Stevens. The serial stars Colin Baker and Nicola Bryant as the Sixth Doctor and Peri Brown, respectively. The Twin Dilemma was the first to star Baker.
 
The serial follows the Doctor immediately after regenerating as he works to prevent the alien gastropod Mestor (Edwin Richfield) from plotting to explode the sun of the planet Jaconda to scatter his eggs throughout the universe to conquer it.