A Doctor Who, Friends and Big Bang Theory crossover episode:

The one with Sheldon in it

After failing to cope with recent changes when Penny and Leonard decide to get married, or finding another field of study, Sheldon implements his plan to create a race of robots to rule the world. The Doctor and Clara intervene to thwart his plan, but only Amy can persuade him to stop.

Return of the daleks
Cybermen return in another small change.
Davros walks
The fireplace in the girl
Rose again
Mrs master
The slitheen master plan