Charlie: He called me Sir! How cool is that?
Vik: That's nothing, someone called me a "bloody Paki" yesterday, how cool is that?!
Charlie: How exactly is that cool?
Vik: Well, old school insults are making a comeback which I find reassuring.
Rob: What do you bring to the party?
Charlie: Well, I can prove Fermat's Last Theorem!
Kylie: Don't men know how to floss?
Rob: Looks like your tongue was doing it for him!
Rachel: Give me some news.
Vik: Running a bit low on courgettes!
Charlie: (Voiceover at the start of the episode) A nuclear attack on London. In bomb terms the blast was relatively small, but the death toll wasn't. Over 100,000 incinerated and many more given a death sentence by radiation. For some people outside of the blast zone, life continued almost as normal, but after the attack nothing in our country would ever be the same again.
Scenes in a shopping arcade were filmed in the Victoria Arcade in Leeds, with the cast nipping in and out of shops, including Harvey Nichols.
The Region 2 DVD of season 1 will be released on September 8th 2008.
This episode was watched by 810,000 viewers.
Working titles for the series included Rogue Spooks and Spooks: Liberty.
Casting for the series originally began in June 2007.
The series is also broadcast in high definition on BBC HD.
The series was officially commissioned by Jane Tranter, the BBC's "Head of Fiction".
Charlie: Well, I can proof Fermat's last theorem.
This is a reference to a medieval mathematician Pierre de Fermat. In 1637 he wrote in his book that he has proved mathematically a certain statement in number theory, but he didn't write the proof itself. It took 357 years for the rest of the world to proof Fermat's statement. In 1995 British mathematician Andrew Wiles published his proof of that theorem, thus ending one of the oldest riddles in the world of mathematics. Simon Singh published in 1998 his book Fermat's Enigma telling the whole story of this riddle from its conception till the solution.