10 Most Horrific Moments In Doctor Who

4. Cyberconversion - Various

Ah, Cybermen - the Borg haven't got a thing on you. At least if someone is assimilated by the Collective, there's a glimmer of a hope that they can be recovered, then given a nice hairdo and a hot outfit to make up for their troubles. With Cybermen, all that's left afterward is the brain - and, it seems, the skull. Since its introduction in 1966, cyberconversion has always terrified us, combining both psychological and body horror in one ghastly package. While we never actually got to see anything near a full-on cyberconversion until Attack of the Cybermen in 1985, we always figured it had to be a nasty process. Seeing possessed humans who had lost all memory of their former lives in those early stories was bad enough, but then the '80s came along and showed us what a true nightmare it must be. You end up feeling sorry even for the Dalek duplicate policeman who gets captured for conversion, let alone Lytton and his poor crushed hands. Then along comes the new series take on the Cybermen, which really brings on the nightmare fuel. At least in the past we could imagine the conversion process as somewhat slow, even painless, and not terribly traumatic - but from Rise of the Cybermen onward, we'll now always think of cyberconversion as involving computer-guided buzzsaws, laser scalpels, a lot of screaming...and "The Lion Sleeps Tonight." That last bit is the worst, of course. Even the partially converted have squicky earpieces that go all the way into their brains. And to top it all off, The Big Bang reveals that the former human's skull is still in there, intact. Shudder. Of course, a lot of this is negated by the revelations that cyberconversion can be reversed through the power of love (thanks, Gareth Roberts) and that cyberconversion isn't all that different from assimilation after all (thanks, Neil Gaiman). But not enough is negated to make it look any more attractive to kids - or to adults. And speaking of transformations...