He's played Tony Blair, David Frost and Brian Clough to understated, award-winning effect, and currently Michael Sheen is as straight-laced as they come as a buttoned-up doctor in TV's Masters of Sex. It goes without saying that Sheen has carved a path for himself as a chameleonic actor able to believably embody real-life figures. But does anyone remember him as Tron Legacy's Castor, the slimy bar patron with ice cream hair and a disco cane made out of fluorescent blue crystal? Probably not, because Castor has inexplicably been left out of the Michael Sheen narrative. God knows why - Sheen's performance as Legacy's Castor is only completely off-piste, like David Bowie dropped some bad acid during his Thin White Duke period and just stayed that way ever since. Everything about Castor just seems off: the transatlantic accent, the effete body language, the fact that his in-house DJs are played by Daft Punk. You can only wonder "why?" as you marvel at the awful brilliance of this character.