So, apparently, drilling beneath the Earth’s crust and releasing a green ooze that turns people into monster men is a really bad idea.
And that’s more or less what happens here as the Doctor is prevented from stopping the drilling in Fascist England from breaking through the crust. It starts with an earthquake, birds and snakes, and airplanes, and Lenny Bruce is not afraid. Can it be stopped? The Doctor and another man, drilling expert Sutton, try to turn it off, but Stahlman is inside the very hot room as well, and he attacks Sutton and tries to drag him into the ooze before the Doctor can intervene. Then Sutton has to save the Doctor, but the two get out and lock Stahlman inside, and Stahlman’s next move is to drag the unconscious technicians over to the ooze to make more of what Wikipedia tells me are called Primords.
So, anyway, this Earth is doomed, but the Doctor may be able to get back to his own universe if the Brigade-Leader and Security Officer Elizabeth Shaw are willing to let him use their reactor to get home. The Brigade-Leader is unconvinced, causing the Doctor to use the last of the TARDIS’s back-up power to zap himself 15 seconds into the future. Besides, the Doctor can only take himself back. Taking anyone else back from the doomed, parallel world would only destroy both universes.
So, apparently, this universe doesn’t have a Doctor. That’s potentially good to know.
But back at the Control Center, where the Doctor would need to reroute the energy needed to get the TARDIS charged, there’s really only Sutton, Liz, the Brigade-Leader, and one Dr. Petra Williams left because they thought they heard Stahlman inside the core, and then when they opened it up, all these green werewolves came out, infecting a soldier and forcing the rest to hide inside the Brigade-Leader’s office. It looks like everyone except the Brigade-Leader is inclined to believe the Doctor and may even want to help him. Heck, Sutton at one point mentioned he was in a secret resistance group. There may not be much anyone can do when they’re trapped by Primords on a dying planet, but the Doctor says he has a plan. Besides, he’s pretty sure he can get back to his own world in time to stop the drilling from going this deep.
And then a Primord breaks through the office’s door.
Oh, and back on the Doctor’s version of reality, the guy in charge of the program got sidetracked by Stahlman and looks like he had a traffic accident, basically meaning only the Doctor can save the day now.