3. Dimensions In Time (Children In Need, 1993)
The Doctor has travelled to the furthest reaches of the galaxy throughout his time as Defender of the Universe, but in 1993 he finally met his match when the TARDIS materialised in the Queen Vic. In a two-part Children in Need sketch, Doctor Who joined forces with the BBC's long-running soap opera EastEnders in a crossover adventure featuring multiple Doctors, companions and Kate O'Mara's last televised performance as the renegade Time Lord, the Rani. Broadcast after Doctor Who's cancellation in 1989, Dimensions was the subject of intense debate amongst the inner circle of Doctor Who fans, as it suggested that Doctor Who shared its universe with the inhabitants of Albert Square. Still, canonical controversy aside, it managed to add £100,000 to the Children in Need total that night, and that's what counts, right?