You know, I don’t think the Master is at good at being evil as he thinks he is.
Why do I say that? Well, when last we saw, he had the bright idea of just shooting Jo and the Doctor while no one was looking, but that didn’t happen because that Ashe guy came along and the Master couldn’t have witnesses. Why not kill Ashe and his daughter too? I dunno. He only had two bullets?
As it is, the colonists, for the second time in a row, beat the mining guys in a firefight. For a crack security team, those guys kinda suck. Winton is going to use this embarrassing defeat to confiscate all the security team’s weapons and make them leave the planet. That makes sense. Sort of. The miners go.
But the Doctor does raise a good point to Ashe and to Winton. Why not check the Master’s credentials and actually make sure he is the Adjudicator? After all, that should be easy enough. But Ashe is busy and Winton doesn’t trust either the Doctor or the Master since neither one of them actually offered up some ID or anything. But the Doctor has another plan, namely to go search the Master’s TARDIS. He did come in a spaceship, and that would be an easy thing to disguise a TARDIS as. Plus, the Doctor still has a key to the Master’s TARDIS. Sure, he and Jo need to sneak under the security beam, but that means the Doctor has free range to search for whatever it is the Master wants.
But then we see someone actually did listen to the Doctor? Was it Jo? No. She tripped the security beam, and a knock-out gas puts both her and the Doctor out. Was it Ashe or Winton, checking the Master’s credentials? Nope.
It was Evil Captain Dent. And sure enough, he sees the Master isn’t really the Adjudicator. So, the mining company goes back, lands somewhere else, gets the drop on the colonists, and since the Adjudicator, who had ruled in their favor, isn’t around, Dent puts Winton and Ashe on trial for treason, saying he is in charge of the planet because the absent Adjudicator said so.
But he knows the Master isn’t the Adjudicator! That stinkin’ liar!
Anyway, he’ll let Winton and Ashe live if they and all the colonists get on their ship and leave right away. Too bad their ship is a death trap that probably won’t even make it off the planet without exploding. Sure, Caldwell tries to get that through to Dent, but the only message Dent got out of it was to have his people not get too close to the ship when it takes off.
But what does the Master want? Simple. There’s a doomsday weapon on the planet in the natives’ city. He wants the Doctor to take him there, and if he doesn’t, well the Master left Jo in a tube that will flood with poison gas if the Doctor doesn’t play along. So, the Doctor takes the Master to the entrance to the city, where the Master fends off some attacks from the natives and the Doctor knows it probably won’t go well for the Master inside the city.
It may not go well for Jo either. Caldwell and another guy get into the Master’s TARDIS using the Doctor’s key, and when they trip the alarm, the Master decides to turn on the poison gas in Jo’s tube…