Didoan

The Dido people were a peaceful humanoid race native to Dido.

History
When a spaceship crashed on the planet in 2493, the Dido people met with the surviving passengers, but were killed along with them by Bennett to cover up a murder he had earlier committed. At least two of the Dido people survived, and when they confronted him, he backed away in fear and fell from a rock ledge to his death.

After the First Doctor's TARDIS left Dido, the Dido people wrecked the spaceship's communications system so that the approaching Earth rescue ship would never find the planet. (TV: "Desperate Measures")

Behind the scenes

 * The Rescue doesn't give us a clear, one-word demonym for "a being from the planet Dido". The name Dido people is what the First Doctor directly called them in "Desperate Measures". The Time-Travellers' Guide refers to them as Didoi.
 * The appearance of the two Dido people in "Desperate Measures" is never explained.
 * The two Dido people were played by John Stuart and Colin Hughes, who were uncredited both on-screen and in Radio Times.