Primeval's co-creator and executive producer Adrian Hodges is being kept busy, as he prepares the new version of Terry Nation's Survivors alongside pre-production on the third series of Primeval. He looks back over the development of the series with Paul Simpson...

Were you asked to increase the serial element in the second season of Primeval?

It was what I always wanted to do. Primeval I hope plays in different ways to different audiences. Our timeslot dictates that we're a family show, so when we first started, we wanted to push the story of the week forward because we weren't quite certain how young our audience would be.

As the first series developed, I felt that we were playing well, so we could begin to be more ambitious with the serial element. When we came to plan the second and third series, there were stories we felt could be told over a long group of episodes. I don't think the serial element is taking up much more time in the episodes; it's just a better story, which is making more of an impression.

Did the relationship between Stephen and Helen occur in Cutter's original timeline?

Yes it did. The view that [executive producer] Tim Haines and I hold clearly is that it absolutely did happen and everything in Cutter's old life, up to the point where things changed, did happen.

Does the 'reset world' have large changes or is it confined to elements that affect the team?

We talked a lot about the implications. We have taken the view that changes have happened, large and small. One of the larger ones happens to have involved our set of characters, but that doesn't mean that there aren't larger ones out there in the world as well, but we have simply not addressed those because they're not what we're doing in our show. However in episode seven, Helen does briefly address her theory about what may have happened. I'm not saying it's any kind of answer but it is a theory about the fact that it may be random nature, but there may be a pattern to it as well.

How much of the series two plotline did you know when you were writing the first series?

I wrote the pilot for Primeval, which at that time was 90 minutes, nearly five years ago. I then wrote another two episodes when the project was still at the BBC, so there were three completed episodes before we went into full development. I think the first three are a mini statement of intent, but the serial story starts to take off after that, because that's when we knew we were going to be in business for at least a year. The effects are great, and there's a lot of things in those episodes that I'm very proud of but they are definitely of an earlier time.

At the outset, two things were going to be different. Hannah and Stephen were going to be a couple, but that just didn't work out – it was quite clear that the chemistry was going in a different direction. I also suddenly saw an opportunity for a triangle between Cutter, Stephen and Helen, which was probably at the back of my mind, but I can't claim was consciously there, when I wrote episode one. That began to evolve out of discussions Tim and I had around the point where we had written episode three.

I'd love to know what [Heroes'] Tim Kring or [Lost's] Damon Lindelof and Carlton Cuse would say about this: certain things you plan and think you can make work over however long an arc, but sometimes you see an opportunity from the way something's played and you think it's too good to throw away.

Where did the idea of the Anomaly Research Centre come from?

When we decided how to play the Claudia/Jenny and Cutter/Helen arcs, we felt it would be a really good opportunity to reset the look of the show. Given that we had a reasonable justification in the changes that had taken place, we felt the show needed a base that looked convincing as an arena that people could experiment in, store things in and cage creatures in. Now that it was a fully-fledged Government-based enterprise, it would have a base. And we wanted it to look really cool!

How long has the ARC been there?

I haven't pinned down the exact timeline but it would have been originated with the original event. It wouldn't predate Cutter's contact with the original anomaly.

How much guidance do you give the other writers?

We tend to storyline pretty heavily. We do that collaboratively – take Paul Cornell as an example. He came in when we had already originated something between two and five pages of the storyline we wanted to tell in episode six – not just the serial elements which obviously have to be there for continuity, but also the story of the week. We would then go through that with Paul and ask him to write his own treatment. He then brings in his own ideas, and we discuss them.

Writing and developing a show like this is genuinely organic. You can't say, ‘This is the way the story will work and don't deviate from that.’ We’re always open to the better idea, but we normally say this is the storyline that we want to pursue this week, this is the setting. The good writers will then say, ‘We could do it like that, but why don't we try this?’ If it's a better idea, then great. We're not dictatorial – or at least I don't think we are! Action sequences can change, and they do when Framestore get involved because there's a maximum number of effects shots you can use.

Have Framestore started coming to you with ideas for monsters?

No, they don't do that. The creatures and the conceptual design is very much Tim's field. When we sit down for story discussion, he'll say, "That story is interesting because I think that creature would work very well in it." In the case of the future creatures, which we're increasingly using, he'll say, "Wouldn't it be great to have a creature like this?" usually based on some genuine scientific fact which he'll then extend logically into an evolved creature.

He'll then go to the chief designers at Framestore, and that's where they come into their own, because they'll say what we can do to make it better. Modifying is too mild a word for what they do. The Future Predator is one of my favourite things we've ever done, and that owes an enormous amount to Framestore.

Have you ever looked at an effect on another show and thought there's a good idea?

No, never. I find myself in a bit of an awkward position. I don't watch the runs of Doctor Who and Torchwood while I'm writing. I catch up with them after the event. If I do see something I admire, or is coincidentally similar to something we've done, I get upset. I wish I'd done it like that – or I can't do that now because they've done it. It's easier for me to not watch those things.

Will the first episode of series three continue from the cliff-hanger to series two?

That will be a reset because of the things that happen at the end of episode seven. That is more to do with character things rather than changes that are as dramatic as at the end of the first series. It will carry on more or less in real time.