And so we get down to the nitty-gritty of the third ever episode of Doctor Who. There's more pre-filming, the Doctor proves that as well as being an old fashioned hero he is also a potential murderer, and his intended victim turns out to be an actor with a colourful and ultimately tragic personal story. Toby Hadoke is your host, with the When, What and Who of this instalment of TV's most iconic science-fiction series of all.