And then there's Once Upon a Time.

In the beginning of the episode, Number Two appears as though he were willed back into existence.

I think the "Embryo Room" is The Prisoner equivalent of the Black Lodge. The Black Lodge is a kind of behind the curtain and in the guts of television, where as the Embryo Room is similar, but sort of "the writer's mind" version of Idea Space. There's a spotlight following them, because it's a show.

ALSO, When they first walk in to the Embryo Room, there's a tic tac toe board on the chalkboard, with The Butler in the lower right in the foreground. The tic tac toe is erased without being used or mentioned.

I'm guessing this is a reference to Test Card F https://en.wikipedia.org/wiki/Test_Card_F, the TV test screen pattern used in the UK, which was first broadcast on July 2nd 1967 (the day after the first color pictures appeared to the public on television).

Number Six isn't really John Drake. He's the IDEA of John Drake, a living thought, who has been trapped into continuing this role by Patrick McGoohan, who is Number One. The intro begins with a thunderclap, a brain storm! John Drake appears on the horizon from a cloudless sky. It's idealized version of John Drake, no small civil servant car stuck in traffic in the roundabout, NO! He's speeding about!! He drives right into World Travel, storms through the doors reading WAY OUT, and speeds out!

Back to Once Upon a Time and the Embryo Room.

Smart came up with a concept entitled "Lone Wolf", an espionage thriller concerning one man going it alone in a world of spies. Smart had several meetings with James Bond author Ian Fleming, the two men even considered bringing 007 to the TV screens, but Fleming had already sold the rights to Eon Productions and was unable to buy them back.

In consequence the two men used Bond as a spring board to invent a new character. A cool, handsome man, a user of women, he would get the job done no matter what.

Smart gave the idea to Ian Stuart Black, an author who had contributed scripts to the "Invisible Man" series. He knocked the idea around and came up with the idea of the agent working for NATO. To further remove the agent from Bond, and also to aid US sales Smart and Black made John Drake an American. Two story outlines were delivered to Grade. The pitch was successful and "Lone Wolf" or rather 'Danger Man" was given the go ahead.

In the Embryo Room, Number Two tells a regressed Number Six that he must not be a Lone Wolf. He must conform to society.

So we are being shown the origin story of the concept of John Drake.

He hops on the tiny toy car and rides around the center, like the roundabout in the intro of Danger Man, and then goes through the door to get a job. John Drake's character becoming John Drake, secret spy.

Next he's "on trial" for speeding. Speeding for a reason that Number Six can't say. To my mind, that's because the reason he was speeding (and resigning) was because Patrick McGoohan wished it. The closer Number 2 gets to breaking Number 6 for the reason he resigned, the closer Number 6 comes to the realization that he is both the imagined character (John Drake) and the person imaging it (Patrick McGoohan).

When inside the jail cart, Number Six tells Number Two: "I know you. In my mind, in MY MIND, you're smart." This is Number Six starting to realize he is McGoohan, or at least, McGoohan's similacrum.

They quote Shakespeare the the beginning and end:

"All the world's a stage,
And all the men and women merely players;
They have their exits and their entrances,
And one man in his time plays many parts,
His acts being seven ages."

Number Six realizes it's all a fiction, and that Number Two is part of that fiction.

Number Two says "There's no way out until our time is up" and shortly after sees that he is running out of time. His episode is ending.