How long did it take you to write the show's final scene?
"Probably an hour. It was one of those things where if you look too hard for something you'll never find it. I was very, very aware that the last few moments, particularly on a real time show, needed to mean something. I was so inspired by The Sopranos, which I felt commented on the medium. Someone once described it as David Chase as a rockstar who took the guitar and just smashed it on stage. And in this case, Jack has this relationship with screens and with us and the idea of us being in Chloe's point of view. In many ways, Chloe has kind of been our proxy for Jack, and the idea of the words that Chloe says - 'Shut it down' - was to me that punctuation mark. Once I had that image in mind that we were going to use this drone... It was like we had no idea that that was going to be the last governing image of the series, but seeing it blink out to static and then to silence and the clock really felt right, and I knew in that moment it was the right thing to do - Jack looking up at us vulnerable, but still living to fight another day."
How long did you have that image for?
"A week or two before the script was due. This whole series has been this protracted exercise in faith that there's going to be an idea there around the corner even though it looks like there's nothing. So it has required patience and bizarrely enough this belief in one's unconscious or in the creative process. I knew more than the detail. I knew the feeling I wanted to elicit when people watched it. I really wanted people to be leaning forward in their chairs and wanting more. I wanted them to miss the show the moment it ended. I knew the emotion I wanted to conjure - I didn't quite know how I'd conjure it."
So you always had some idea of how you wanted it to end?
"I knew the feeling I wanted to elicit rather than knowing the moment itself. I knew it couldn't be a happily ever after. I didn't want people to feel good and I didn't want people to feel bad. I wanted them to feel somewhere in between."
How do you think the show changed over the series?
"I think it's almost like a romance. A romance is so intense when it begins and because of its newness it's very vivid and it's very exciting and suddenly you're married 25 years. It does gain meaning because of its longevity - because of all that we've been through together, the people behind the scenes and the audience we've shared this show with. It has a context that's very deep and very meaningful. I think the beginning was more exciting, more vivid, more revolutionary and the end was deeper and more wistful and more elegiac."
There was some criticism of the way you changed the character of President Taylor in the eighth season. How do you respond to that?
"To me, because we were ending the show, we had to take some chances. I knew I wanted Jack in this very dark place. And Kiefer and I, we discussed this, that this Renee relationship was going to build up to a point of some kind of consummation and Jack is going to have the hope of something to live for and that will be taken away from him. And again, people hated that too. Everyone's going to hate something. You really have to go with what you believe is the best story and hope in the end that people will still watch. But in the case of President Taylor, her moral compass was so straight and so fixed and so true, and so I thought for her to lose herself is a very human thing to do, particularly under that kind of duress. I felt like the scaffolding for her momentary lapse was there. She wanted this peace accord so badly, she'd lost her own family in the service of this peace. We all get out of joint, we all get disoriented, and she's exhausted. She's a heroic person and she's been so true and that's what's surprising. For her just to continue to make the right choice time after time gets monotonous. For her to have a lapse and to become a monster, to be distorted by her power and by her aspiration and by her fatigue, felt exquisitely human. Believe me, we struggled terribly getting it right. But we got it right, I think. I think at the end, knowing that Taylor could resurrect herself or pull herself out of the nosedive and by the way, not undo the damage she's done, but save her character. But everyone was like, 'What are you doing?'. And I said, 'Trust me'. I didn't know, even when I was saying 'Trust me', that it would work. You must be willing to take chances and fall on your face. That was a liberating feeling to say, 'You know what? F**k it, I'm just going to try it. I think it's right'."
You said you think you got that right, but do you have any regrets about things you've done in 24?
"I hope it doesn't sound arrogant, but I don't. There are things that I'm not particularly proud of, which I'd separate from regrets. There are some bad moments, there are some moments that really don't work and characters that don't work. But a regret implies that I should have made a left instead of a right-hand turn and I can't think what else I would have done. I feel like I explored every possible option, whether it's Kim's cougar moment or whether it's Teri's amnesia or whether it's many parts of season six - I don't know what else I'd have done, even in retrospect, so I can't say that I regret them, just that there are things I'm less proud of."
Aside from Jack, the only other character that appeared in every single season was Aaron (Glenn Morshower), so why wasn't he in season eight?
"We desperately tried to find a place to put him in and just could not find a place to wedge him in without feeling like we'd wedged him in. I love him. These actors have become such great friends and we're so lucky to have been with such great people. And yeah, we talked about it, but couldn't find a place."
Did you think about bringing back Tony (Carlos Bernard)?
"That's another great question because in season seven I think we had perhaps overplayed that hand, so to me his story's been told and probably retold. That was once where you really have to say, 'This is really it'. I mean, look at Logan. Every one of these resurrections are always fraught with their own kind of peril and you have to use them very judiciously. We considered it but something in my head said that's really not going to happen."
Season eight of 24 was obviously the final one but had you seriously discussed a ninth season?
"I had serious discussions with Fox to the extent that I said this was my last season and if they wanted there to be a ninth I would help them find my successor and groom that person or people. So I entertained helping them transition to the infrastructure of a ninth season, but I think in the end Kiefer felt that this was really it and I felt it. Knowing that I was not going to be back may have informed his decision, I don't know."
Why did you decide not to continue for a ninth season?
"I felt frankly that season seven was so challenging for me that I was ready to call it quits, and I was convinced to stay on. But very much to stay on with the idea that this is it for me. I knew it was for the end for me. We had a series of talks about who might take over the show, and I think soon it became pretty clear that it was just not practical to do that."
You've mentioned before that you thought about killing Jack. Did you ever get as far as thinking about how you would have killed him?
"There were two things. I thought of killing Jack in a very off-centre, syncopated way, where you're not expecting it. Kind of in the margin of the scene, just suddenly, and you're left with the rest of the story. But I think that would have been unrecoverable. And then I thought at the very end, the show is a tragedy, and there would have been a moment to kill Jack, where Allison Taylor tries to stop him like Romeo And Juliet but she's too late. She saves herself and stops this crime from happening but Jack has to pay the price. And Jack ultimately would have had to pay the price for all the bad things he's done as well. There was a symmetry to that and I think that might have worked. I think it would have been very depressing and I think that's the reason why in the end this is a superior way to have ended it. We contemplated it and I think Kiefer was up for it if it was the right thing to do, but I think no-one was prepared to say goodbye to that character and that trumped the surprise or the shock or even the symmetry or the narrative correctness of Jack's death."
Freddie Prinze Jr.'s character Cole seemed like a younger version of Jack. Was that the intention?
"We've had a couple of so-called younger Jacks, whether it was Ricky Schroder or James Badge Dale. Jack is Jack. Yes, what they share is they're men of a certain age, they're men who are good at what they do, but they're all different. The person who's closest to Jack would be Renee. I think she's the only one who really had a trial by fire, who really understood Jack's soul. She's probably the closest to a protege that Jack has had. These other guys were partners and you learn pretty quickly that it becomes kind of a buddy movie, and Jack is a solo act."
Did you ever think 24 could have continued with Freddie Prinze Jr. in the lead?
"That was briefly an idea that we flirted with. He's someone who also is a bit of a boy scout when he starts the season and then of course he learns that he's married to a murderous spy and all the assumptions that he began the day with were all false. It was sort of the education of Cole. I think Freddie did a fantastic job. At the beginning of the season, he got some crap for that casting and I think he's actually a real leading man and conducted himself just beautifully."
Moving on, how far along are you with the 24 movie?
"There is a script. It's being read by Fox now. There's no schedule, there's no green light, there's no plans right now in terms of a calendar for it. But we're working on it."
Did you learn many lessons from 24: Redemption when you were working on the movie script?
"Well, Redemption was its own sort of animal in because it was a prequel that was written after seven episodes had been written of season seven so only so much could happen. The only lesson we learned was that it felt like you could take a two-hour chunk outside of the 24-hour framework and present it and have it be compelling on its own merits. We learned too that Jack in an exotic locale is compelling. By and large it was a successful exercise. I was very happy with it. I did it grudgingly. Fox came and said, 'Can you... not can you but you will do this', and I was like, 'First of all, how can you tell me to do it, I don't have an idea yet'. I'm glad they did."
You just mentioned it's good to see Jack somewhere exotic. There have been lots of rumours that the movie will be partially set in the UK. Can you say anything about that?
"Right now the UK is a location, Prague is a location and Serbia. And China."
Do you think there'll be more than one movie?
"I think the intent is actually hopefully to build a franchise and [writer] Billy Ray says he's got three."
When does the movie pick up after the end of season eight?
"It's roughly 18 months."
Can you tell me anything about the plot?
"No. Only because it's such a work in progress that anything I say could be invalid tomorrow. We're a couple of weeks away, I think one way or the other we'll know more shortly."
What about which cast members will be back?
"I can tell you... again even that is way subject to change, but right now I can tell you that Chloe... How about Chloe, I'll give you Chloe."
Go on, you were going to say more then!
"I was, but again that could go away, it truly could."
The 24 season eight boxset is available now.
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