"You'd exist twice over. And if the two of you met, you'd short out the time differential. Don't you see? The Blinovitch limitation effect? Oh dear. As Tegan would say, zap!"
IN THIS ONE... Everybody convenes on the ship in the same time zone, including two Brigadiers, and Mawdryn is exposed as "not-the-Doctor".
REVIEW: Wouldn't this serial work a lot better if Mawdryn looked anything LIKE the Doctor? As it stands, between the repulsive exposed brain and the gauzy robe that magically regenerates with him, there's absolutely no reason for everyone to go "Doctor? Is that you?", including the older Brigadier who KNOWS what's going on, much less Nyssa firmly insisting they have to trust him. Well, I'm wearing my TEAM TEGAN for the duration. It is so patently obvious, the characters are just made to look like dunderheads. Are they confused by his draping himself in what looks vaguely like the 4th Doctor's burgundy coat? Ugh. Aren't they listening to what he's saying? Why does Nyssa think she's helping the Doctor when he seems to be asking for his life to end? The dialog is atrocious across the board, mind you, and it seems completely counter-intuitive to have a character who wants the Doctor's regenerations so it can END his life. What the what?
At least the truth is revealed by episode's end so the characters can stop with the obliviousness already. Mawdryn's people got a hold of regeneration technology (cementing the idea that this is not a natural condition, in spite of more recent evidence) and tried to gain immortality, a crime for which they were exiled aboard a luxury spaceliner (err?), though it of course backfired and now they're just mutating and deteriorating in an endless loop of failed regeneration. I guess. The nonsense cliffhanger "Helping you would mean the end of me as a Time Lord!" means they need the Doctor's extra lives to kill them, though stabilizing them would seem the more coherent idea. How can extra lives kill? Complete hogwash, thanks again, Mr. Grimwade.
So where does this episode actually LIVE? In Turlough, mostly. We're still getting to know him, and just when he seems an unfortunate Adric wannabe (another tech-head whom Tegan dislikes), the Doctor makes a face at the brazen alienness of this apparently human boy. I love how the relationship plays out, with the Doctor throwing him his Black Guardian communicator, not saying a word, waiting for Turlough to come clean (though he merely suspects him of being an alien, not a Black Guardian pawn). The Black Guardian has another cool spookshow moment when he is superimposed on a bust, though he couldn't be more one-dimensional in his evilness. There are some amusing moments with the Brig too, showing off his famous obtuseness. With two of them, there's a chance to put a mirror up to his interactions. So he's a chauvinist who relegates the girls to babysitting the TARDIS in one time zone, and of course, is the one mumbling about being told what to do in the other, as the Doctor still gets the better of him.
VERSIONS: The CGI option gives the Black Guardian a certain glow without removing what was clever about them in the first place. The distortion on the transmat capsule is still nice. But the energy flow added to Mawdryn's regeneration machine is a bit of a bust, fake and spilling over the lines.
REWATCHABILITY: Medium - The plot is complete bollocks, but character moments manage to buoy the episode up.