Its always important for any TV show to have a good cast. If your actors cant make the world of the show believable, there isnt a lot you can do to save it. However, the entire cast is on fire here. Tom Baker is already showing the charm and eccentric edge that make his Doctor quite so enduringly loveable and that means there is never a dull moment. Harry is often one of the most underrated companions in the history of the show but here Ian Marters performance means he has one of most interesting first trips in the TARDIS. Marter really sells the idea that Harry is out of his depth but is still likeable enough to make fans stay on his side. Elisabeth Sladen as Sarah Jane, meanwhile, gets generally less to do but she is still just as brilliant as always, adding little touches to her performance to deepen the ongoing relationship between the central characters. Theres great chemistry between the three leads - partly why theyre often seen as one of the best TARDIS teams - and that contributes to just how well their interactions play out on screen. Its not only the main cast who deserve plaudits, however. Each of the guest actors manages to create a believable character with their own traits and personality, even when their screen time is limited. As well as making for something thats great fun to watch, this deepens the whole world of the Nerva Space Station, on which the story is set, and makes it seem more real, despite the occasionally dodgy sets and space effects. Speaking of dodgy effects, extra kudos has to be given to actor Kenton Moore who plays Noah, the leader of the space station. Hes the one who has to deal most with the monster design (the Wirrn larvae are made of green bubble wrap - no, seriously!) and its his performance that means that the worrying effects dont actually matter. He makes the conflict his character faces when infected by the alien menace really believable and in doing so completely sells the threat of the Wirrn. So if for no other reason, watch it for Kenton Moore.
