"Play in 3 Acts" and "1, 2 & 3." were the original titles of this episode.

The opening sequence is slightly different: Number Two says "I am Number Two," omitting "the new." Although this episode aired before "The General," it was produced after that episode. The intent was to convey that this Number Two, played by Colin Gordon, was not new but had in fact opposed Number Six before.

Number Two: (viewing Number Six's thoughts) Extraordinary. How very single-minded.
Number Fourteen: He's not conventional.
Number Two: I sometimes think he's not human.

Engadine: And remember.. you're mine.
Number Six: Really?
Engadine: Be horrible to other women.
Number Six: I promise.
Engadine: Oh, thank you.

"A": News of old friends travels quickly.
Number Six: In a few hours.
"A":To you and to me, news is like air. We breathe it deeply. We draw it from far and wide.
Number Six: If it's interesting.
"A": What are you going to do with your freedom.
Number Six: Go fishing.
"A": Perhaps you're fishing now.

Number Six: You never could take a hint.
"A": I don't want a hint. I want you.

Number Six: Last week, Number Fourteen was an old lady in a wheelchair. You're new here, and you're one of them.

Madame Engadine: Men always evade questions. All my husbands did.

Number Six: He may return.
"B": Oh, being killed is an occupational hazard.
Number Six: Like a sitting duck.

Number Two: What's that Number Six doing? Always walking. Irritating man. Doesn't he ever get tired?!?

Blonde Lady: You're young to retire.
Number Six: Age is relative.

Torture
This is the first episode (in air order) where there is a serious effort to break Number Six. Despite his supposed value, Number Two isn't shy about putting Number Six in harm's way to assure success. The episode's finale is Number Six's most clearcut triumph of the series, and an indicator of the Insurrection plot as he turns the tables on his captor.