In Doctor Who:
The Yeti first appeared in the Doctor Who story The Abominable Snowmen, and returned in The Web of Fear, both times opposing the second Doctor (played by Patrick Troughton), and for a brief cameo in The Five Doctors. The appeared in the comics for the first time in Yonder...The Yeti, a back-up story in Doctor Who Monthly.
The Yeti are robots constructed by individuals who have been taken over by the bodiless intellect of the Great Intelligence. Initially utilised in Tibet, the Intelligence later set up base in London using one of the Yeti robots that had been transported there, and, after replicating additional Yeti robots, it attacked the city, using the London Underground as its base.