10 Longest Gaps Between Doctor Who Character Appearances
2. The Great Intelligence (16,363 Days)
In a neat bit of foreshadowing for the return of almost all of The Web of Fear back to the archives, the big-bad of Doctor Who's 50th anniversary year was revealed to be the Great Intelligence - sans Yeti.
The Great Intelligence made two memorable appearances during the Patrick Troughton era, as a malevolent, disembodied force able to influence those in its grasp.
The best-loved Great Intelligence story The Web of Fear was top of fan lists of lost stories they wanted to see return, and they would eventually get their wish in 2013. Before that exciting day, the Great Intelligence made its first appearance in 44 years, voiced by Sir Ian McKellen in the 2012 Christmas special, The Snowmen.
Hilariously, the Eleventh Doctor has forgotten all about the Great Intelligence, given how long it's been since they crossed paths. This forgetfulness even leads to the Doctor accidentally giving the Intelligence the idea to take over the London Underground in The Web of Fear.
It was another of Steven Moffat's deep-cut Doctor Who references that hinted at the exciting 50th anniversary year to come.