From Eternity (short story)

Summary
On behalf of the Time Lords, the Doctor interrogates a being responsible for deaths beyond counting. The entity believes itself to have been the first intelligence born into the Universe, and it spent aeons of darkness alone until it saw the first speck of physical matter come into existence. As further aeons passed, it saw the first stars blossom, and eventually it made contact with an intelligent species, only to see the species devolve into savagery, gradually becoming less sentient until all that was left was primordial ooze. When the same happened to the next minds that the entity encountered, it concluded that this bizarre infection was built into the nature of the Universe, and, fearing that it would be alone for all of eternity, it tried to warn species of the danger they faced. When they failed to respond to the threat, the desperate entity tried to force them to do so by presenting them more immediate dangers. The first species it destroyed was the Iarcho, and many more followed until it finally learned the truth from the Time Lords: it perceives time backwards, and has been witnessing evolution and progress in reverse. Unable to correct its past (or rather future) mistakes, the entity accepts that it has performed monstrous acts for which it can never atone, and accepts that it will spend the rest of its long life alone until it dies at the beginning of the Universe. But when this finally occurs, the entity discovers that this Universe is just one of many, separated by dimensional membranes that occasionally collide and interact, creating new Universes and new Minds whenever they touch. The entity is at peace, knowing that its long periods of loneliness are merely a phase that will be interspersed with moments of brief and intimate contact with other Minds.

Characters

 * The Doctor
 * The Entity

Continuity

 * The Doctor would later meet another entity which experiences time in reverse in IDW: Room with a Deja View. The Doctor, along with his grandchildren, would experience time in reverse himself in TVC: Time in Reverse.

Timeline

 * From Eternity is the first known event (not counting flashbacks) to occur in the Doctor's timeline.
 * From Eternity occurs after: DWMS: Flashback (flashback)
 * From Eternity occurs before: NA: Lungbarrow (flashback)