The War That Destroyed the Time Matrix
The war that happened between time traveling aliens was a long time. Not necessarily a long time ago, nor was it a long time in the future, it spanned years, traveling between times in the future and past. The war began when a deadly race discovered power that they shouldn't have, and a powerful being (or three) intervened. This is how it happened...
It was a normal day on the Tardis. The (tenth) Doctor and his companion Donna were traveling through time looking for anywhere interesting and fun, but somehow only finding danger, when the Doctor's phone rang-the payphone on the outside of his Tardis. The Doctor looked in shock at the phone ringing outside, then landed in a hurry and stepped out. Donna looked questionably at the Doctor, then the phone. The Doctor answered the phone.
"...Helloo?"
The answer came from what sounded like a merry old man.
"Yes, hello, I need your help, is this the Doctor? Well of course it is, I don't have to ask. Could you come and help me with something? It concerns an alien invasion and a Satan-like entity helping them along."
The Doctor answered in confusion.
"Well, yes, I can, but how did you reach this-"
"Great! I'll see you there!"
The call ended.
The Doctor hung up the phone and stared. He turned to Donna, but before he could say anything, Donna pointed in shock to directly behind him, and it was clear she expected him to look. He turned around. Something strange was going on. There was the old man, standing in front of him with a long beard and robe, the robe growing wispy as it got to the floor.
Oh yeah, and the rest of reality was frozen in time.