During World War II, a group of aliens known only as the "strangers" made their way to Dresden and tried to depart by transforming themselves into code with a quantum resonator. While investigating, in June 1944, the Eighth Doctor asked USAF bomber pilot Captain Joseph Heller to fly him to Dresden but the war-weary Heller refused.
On 12 December 1944, Alan Turing was recalled to Bletchley Park after the strangers' code was intercepted and found to be originating from Dresden. Around 31 January 1945, the Doctor, Turing and Heller embarked on a mission across enemy territory to meet with them in Dresden. At the time, it was one of many German cities being hit by British and American bombs.
Reaching Dresden in February, the Doctor tried to help the strangers depart but he was confronted by Graham Greene and Herbert Elgar. During the encounter, the RAF and USAF launched a devastating raid on the city with incendiary bombs with set the city ablaze, destroying buildings and killing of thousands of civilians. Once the strangers had gone, the Doctor, Turing, Greene and Heller went out into the burning streets to help the survivors. (PROSE: The Turing Test)
Squadron Leader Ian Gilmore, while flying missions over enemy territory, witnessed the bombing of Dresden and tried to put it from his memory. (PROSE: Who Killed Kennedy) The Seventh Doctor listed the bombing of Dresden as one of the terrible things that happened after he set history back on track by freeing the Timewyrm from Adolf Hitler's mind. (PROSE: Timewyrm: Exodus) Chris Cwej later repeated the same sentiments. (PROSE: Just War)