So, to review, the Master managed to get the Xeraphin’s sarcophagus, to say nothing of a mob of hypnotized people, to probably charge his TARDIS and leave the Doctor and company stranded millions of years in the past.
It’s probably a good thing for the Master that most Doctors don’t believe in violence.
But as much as everything went the Master’s way last time, it doesn’t work so well this time. Yes, he had left Captain Stapley and the co-pilot stranded in the Doctor’s TARDIS, floating above the ground. But then a mental image of the late, aptly-named Professor Hayter appeared and guided the TARDIS down to the chamber to pick up Tegan, Nyssa, and the Doctor before zapping out again to get to the flight engineer. The Doctor thinks he can get everyone home in the Concorde they brought with them, but that won’t stop the Master.
What will stop the Master is the fact Captain Stapley’s attempts at sabotage actually worked. The Doctor is impressed.
So, now there’s a plan. When the Master comes back, the Doctor can propose a bargain with a few conditions. First, the Master has to give up all those kidnapped people he was apparently just going to use for fuel anyway.
From there, the Doctor will share some equipment, and it will work exactly as the Doctor said it would. The Master would easily see through any other form of deception. No, instead, it goes a bit differently. Scavenging some spare parts from the first Concorde, Stapley takes off and goes a route the Doctor programmed. Meanwhile, the Doctor zaps away in the TARDIS in the cargo hold at just the right moment, returning the Concorde and everyone on board to Heathrow 24 hours after they vanished. And yes, the part the Doctor gave the Master worked exactly as promised, but he still got his own TARDIS to the exact same spot the Master wanted to land in. He just got there before the Master. The Master then had to materialize his TARDIS somewhere else.
That would be on the Xeraphin homeworld, where the radiation is bound to have died down enough for them to reform physically, and due to some other complications, the Master will be stuck there for a while at least.
And then when airport security shows up, the Doctor just jumps in the TARDIS with Nyssa and takes off again.
Yeah, Tegan finally got to Heathrow to start her job. Too bad she seems to have maybe changed her mind about all that.
Then again, next episode starts the shows twentieth season, so I expect there may be some reunions and the like over the next few serials before the big 20th anniversary special brought back, well, as many people as they could.