Omega makes his big entrance and tells the Doctor
"In the legends of your people I am called Omega."
At least he's not called Omicron, mew.
Omega calls the Doctor "brother Time Lord" and has Dr Tyler and Jo taken away so that he can talk to the Doctor alone and tell him about his "revenge." This scene is full of exposition about who Omega really is and what his motivation is, so it is worth quoting in full:
Omega: "Without me, there would be no time travel. You and our fellow Time Lords would still be locked in your own time, as puny as those creatures you now so graciously protect."
Doctor: "You knew your mission was dangerous."
Omega: "Dangerous, yes, but I completed it, and I did not expect to be abandoned. Many thousands of years ago, when I left our planet, all this was then a star - until I arranged its detonation."
Not content with telling the Doctor things he already knows, he even shows him pictures of it on his TV set.
Doctor: "You were the solar engineer. It was your duty."
Omega: "It was an honour, or so I thought then. I was to be the one to find and create the power source that would give us mastery over time itself."
Doctor: "Well, you succeeded, and are revered for it."
Omega: "Revered, here?"
With my reputation?
Omega: "I was abandoned."
Doctor: "The histories say that you were lost in the supernova."
Omega: "I was sacrificed to that supernova. I generated those forces, and for what? To be blown out of existence into this black hole of antimatter? My brothers became Time Lords, but I was abandoned and forgotten!"
Doctor: "No, not forgotten. All my life I've known of you and honoured you as our greatest hero."
Omega: "A hero? I SHOULD HAVE BEEN A GOD!"
Omega goes to full volume with that last line, as the friendly chat gets suddenly very dangerous for the Doctor. But after a quick cut to a short scene of Jo and Dr Tyler in a cell, Omega has calmed down and is chatting normally to the Doctor again. He even uses his mind powers to create a chair for the Doctor to sit upon.
"Mind, you might say, over antimatter."
Mew. When the Doctor asks what will happen if he refuses to co-operate with Omega's plan, Omega again gets angry super-fast:
"Then you will face the wrath of Omega, you and those miserable humans who accompany you!"
The "wrath of Omega" eh? I thought this plot sounded a bit similar to Star Trek 2 Wrath of Khan. It only needs for Omega to shout "THIS IS CETI ALPHA FIVE!"
Omega gets a telephone call from his creatures to tell him that others have arrived in his world, and we see that the TARDIS has landed back inside UNIT HQ. With the SFX monster too expensive to keep using gone from outside, the Second Doctor, the Brigadier and Benton venture out, with only the Doctor realising that the entire building has been transported. As the Doctor convinces Benton of this, an unfortunate camera angle gives us a rare look directly into the TARDIS prop from outside.
The Brigadier opens the door out of the HQ and sees a CSO landscape outside instead of the environment he was expecting to find. This causes him to do a humorous double-take at the camera.
Brigadier: "Now see here, Doctor, you have finally gone too far."
Second Doctor: "I rather think we all have."
Lol. The komedy continues with
Brigadier: "Do you realise what you've done? You've stolen the whole of UNIT HQ. Now what am I going to tell Geneva, that the whole blessed building has been picked up and put down on some deserted beach? We're probably miles from London!"
Second Doctor: "I'm afraid we're a little bit further than that, Brigadier."
Brigadier: "You mean we're not even in the same country? There'll be international repercussions. This could be construed as an invasion."
Benton: "It's not just a matter of the same country, sir. If the Doctor's right, we're not even in the same universe."
Brigadier: "What? Oh, nonsense, Benton, I tell you that's a beach out there. It's probably Norfolk or somewhere like that."
This scene builds until it reaches the apex (or should that be nadir?) of the Brigadier's stupidity, and one of his all-time classic lines:
The Brigadier's stubborn thick-headedness ends up saving him, since he leaves to look for a telephone, and thus avoids getting captured by Omega's jelly creatures along with the Doctor and Benton.
Mr Ollis finds the Brigadier, hoping that he can explain what is going on, but is disappointed and instead ends up telling the Brigadier what happened to the Third Doctor and Jo in
episode two. They follow the creatures taking the Second Doctor and Benton to Omega's lair.
The Third Doctor is still chatting to Omega when the Second Doctor and Benton are brought in. He attempts a bluff that they are both more mannys captured by mistaik, but Omega is clever and soon realises the truth:
"Can it be? Two Time Lords? Ha! The same Time Lord! The High Council must be desperate indeed to transgress the laws of time."
This helps show Omega is a fearsome adversary for the Doctor(s), although the Second Doctor wastes no time in identifying a potential weakness in him with how quickly he grows angry again - so angry that there is the noise of scary thunder. Omega sends them all to be put in the cell with Jo and Dr Tyler.
Having been reunited, the Doctors fall to arguing again, the Third Doctor even telling the Second
which gets the understandable reply
"There's no need to be offensive!"
because a comparison to Twitter is a deadly insult. It is unclear if the UNIT era is set far enough into the future for Twitter to exist by then, or if the Doctors know about it from having been even further into the future at some point.
Dr Tyler tries to help, but he seems more interested in understanding the science of how the antimatter world exists than immediately practical matters such as escaping or defeating Omega. This is an excuse for the Doctors to give him (and us) some exposition:
"Well, singularity is a point in space time which can exist only inside a black hole. We are in a black hole, in a world of antimatter very close to this point of singularity, where all the known physical laws cease to exist. Now, Omega has got control of singularity and has learned to use the vast forces locked up inside the black hole."
The upshot of this is, as the Doctor says, that
"The only natural law here is the law of Omega's will."
Jo suggests the Doctors could "will up a small door" for them to escape, and this plan succeeds. They all get out of the cell and go looking for Omega's "singularity chamber," but the jelly creatures that are still waddling and milling about the place cause the Doctors to get separated from Dr Tyler, Jo and Benton.
So it is only the Doctors that reach Omega's singularity smoke machine, but Omega catches them right away. The Doctors are defiant:
Third Doctor: "If you free us, we'll plead your cause to the Time Lords. Otherwise we shall combine our wills to destroy you."
Omega: "You dare threaten to destroy me? You wish to fight the will of Omega?"
Third Doctor: "Yes, if I must."
Omega: "Then you shall, but you will fight the dark side of my mind."
The Third Doctor suddenly finds himself facing the dark side of Omega's mind. I think he is meant to have a scary face, but I don't even need Scary Cat's help with this bit, I have seen scarier. It does remind me a bit of Mr Sin from
Talons of Weng-Chiang though. They do some wrestling in slow-motion, which is indicative that this episode was probably under-running.
Meanwhile Dr Tyler, Jo and Benton have run to the front door to escape the jelly creatures. There is something of a Clue moment as they are trying to get out at the same time as the Brigadier and Mr Ollis are trying to get in.
Benton: "How did you know we were trying to get out?"
Brigadier: "We didn't. We were trying to get in."
But when the door does finally open they all run away with the creatures chasing them.
The First Doctor speaks to the Time Lords (his only opportunity to be in this episode), who have somehow found out about Omega - presumably they have been watching this episode on their TV set. They propose sending him in to the black hole as well, because
"All three are needed to defeat Omega."
Back at the wrestling, Omega says
"Those who oppose the will of Omega shall not live! Destroy him!"
I think this means that the Doctor lost the match, even though he still seems to be slow-mo struggling with his opponent. This is the cliffhanger, and it isn't a great one because it is unclear exactly what's going on - what we hear not matching up with what we see.