Tom Baker sits up at the beginning of this episode, and Doctor Who fandom sits up like a bolt at the same time. We've been warned by Cho-Je just prior to The Doctor's regeneration that the new Doctor's behaviour would be slightly erratic. Nothing could prepare us for this, though.
To look back at Tom Baker's debut, knowing all that was to come afterwards, is fascinating to see how it all began. To watch Baker's first few scenes after eleven years of Hartnell, Troughton, and Pertwee, is astonishing. Baker is simply nothing like anything ever seen in the programme to this point. He is immediately aloof and alien, a drastic contrast to Jon Pertwee's portrayal. I mentioned Cho-Je's other quote in my last write-up ("The old man must die, and the new man will discover to his inexpressible joy that he has never existed."). That quote is perhaps even more relevant to Tom Baker's Doctor, especially in this episode.
As much as I love Tom Baker's debut, it is tremendous to see Harry Sullivan come on to the scene, and is it me, or does location OB video recording, which makes its first of several irregular appearances throughout the 1970s in this story, have a charm all its own?