Last year's ITV hit show, Primeval, has returned to UK television with a host of prehistoric creatures faster and fiercer than ever. The return of the family drama on Saturdays at 7:00pm marks yet another success for the ongoing creative partnership between Impossible Pictures and Framestore CFC.

Co-created by Impossible's Tim Haines and writer Adrian Hodges, the seven new hour-long episodes are aimed squarely at an audience hungry for savvy, contemporary drama with a sci-fi edge. The new episodes were directed by Jamie Payne, Andrew Gunn and Nick Murphy.

Framestore CFC supplied the production with seven new CG creatures - and some old 'faces', too - seen in some 350 shots, as well as a further 350 digital VFX and CG enhancements - set extensions, CG vehicles, laser cages and so on. Around 100 people worked over a period of nine months to bring the bestiary to life, up to 60 at any one time.

The second series involved a larger team than the first series, with more animators, compositors and TDs aboard. It was led - as in the first series - by VFX Supervisor Christian Manz and Producer Matt Fox. In order to manage the project, Fox and Manz pipelined the entire project in the same way they would a film.

"Whereas last time around we applied this pipelining to the compositing and lighting to some extent," Manz says, "This time we did it for the whole project - modelling, rigging, animation, the whole shebang was reorganized. The tool set we use for TV is now the same that we use on films, which offers our team the chance to draw on some of the fantastic in-house R&D work that the film teams have built up over the years. It's a fantastic resource. For example, the superb work the Framestore CFC The Golden Compass team did on fur while creating the polar bears for that film was a resource that informed and enhanced our own sabre toothed tiger."

Primeval stars Douglas Henshall as Professor Nick Cutter, an evolutionary zoologist recruited by the government to investigate a series of bizarre creature sightings. Series 1 saw Cutter discovering the presence of 'anomalies' - portals through time (both past and future) from which the creatures were emerging. The new series begins with Cutter's return to the present from prehistoric times to find that Claudia Brown (Lucy Brown), one of his team, has vanished from history.

Only he and his estranged and villainous wife Helen (Juliet Aubrey) know that things were ever otherwise. This modification of history, however, is not his only problem. The new series sees, among other phenomena, a family of raptors going wild in a shopping mall, a sabre toothed cat in an amusement park and a mammoth on the M25.

"We were told midway through the broadcast of Series 1 that we'd be recommissioned," recalls Manz," So we got down to prepping for the next shows straight away. That was in March 2007, with the shoots starting in June. We had briefs for several of the creatures and, in addition to storyboarding and pre-viz, we needed to do some intensive R&D on how we'd be creating the fur and other creaturely elements."

"Another key feature that Matt Fox and I wanted to bring to the second series was more animated faces," Manz continues, "Many of the creatures in Series 1 - often simply because of what species they were - had somewhat rigid facial features. But when it comes to something like the sabre tooth - which is essentially a big cat - or other mammalian animals, the viewers would rightly expect to see something with more mobile features and a greater range of expression."

New to the team this time around was Lead Animator Mark Brocking, who says, "There was a real mixed bag of creatures both real (albeit extinct) and imaginary (based on what might evolve in the future). Some had obvious living analogues - elephants, for example, are a good starting point for how a mammoth could move. Others were trickier. The mer-creatures that appear later in the series are a sort of ape/seal hybrid, so we looked at a lot of seal footage. But we always want to give things a twist, so we altered the way the arm/flipper is hinged, giving it a completely idiosyncratic gait."

As for the facial animation, Brocking says, "We used blend shapes to give the features a much greater degree of nuance, enabling us to tweak elements such as nostrils, lips and eyebrows in a realistic way. So snarls look more natural - and scarier!" In addition, Brocking initiated the creation of a massive online reference resource, offering his team a massive library of real life examples of everything from the flick of an ear up.

Lead Technical Director for Series 2 was Jason Mayo. "The brief for almost every creature included something we'd not tried to do before - we implemented the Framestore CFC in-house fur system for the sabre tooth tiger, we gave the raptors scales and a crest, we used subsurface scattering to give some worm-like creatures a fleshy, translucent quality - really quite creepy, "he notes with relish," And on top of that we wanted to make all of them look even better than the first series' creatures."

The creature work was done entirely in Maya, rendered in Mental Ray and composited in Shake. Flame was also used for some spot effects. The project was shot on film, and in addition to all of the VFX post production, Colourist Brian Krijgsman mastergraded the entire series in Framestore CFC's Digital Lab facility. Keeping it all in-house made for a much more responsive and flexible process, one more readily able to integrate changes and tweaks.

Overall, the Framestore CFC team enjoyed a greater degree of flexibility and input on this project, working closely with the producers and directors to get great looking results within a tight schedule. In addition, the new series gave the company a further chance to bring its expertise to bear on a contemporary prime-time drama, and to raise the bar on what a television audience could expect from their visual effects.