Question: What do you do when you get a nation talking about the launch campaign for your digital TV stations? Answer: Exceed expectations by taking the concept one step further.

The project in question is BBC's face-pulling Talking Heads campaign that launched the broadcaster's eight new digital TV services last November. Created by agency Duckworth Finn Grubb Waters, "Anthem" was produced by the BBC, directed by Tim Pope of Cowboy Films and laboriously posted by Clear, all based inLondon. In the spot, several BBC personalities rip off their faces to reveal another underneath, each speaking about their relevant station.

The second pool of spots reunites the same cast of behind-the-scenes characters and includes two ads that broke in March and April, and a third scheduled for May 2. In "Grannies",a couple of old grandmas chat TV at a bus shelter; a family talks digital over dinner during "Family"; and in "Chippie", a father stands in a local chip shop lamenting his family's desire for better entertainment.

As each character talks about the variety afforded by BBC's digital services, a new face is revealed. However, unlike "Anthem", where the person's body changed with the face, in this series the face changes but the body remains the same. The comic result is newscaster John Simpson's head on a rather rotund granny, and model Jerry Hall's noggin on a short, rather plain mother.

While much was learned from "Anthem" - for instance, timing actors to within one-tenth of a second - the latest batch created a whole new set of problems that kept the team on their toes.

Though simple-looking, the effects are intense. "They're a total mind fuck," says Pope. "It's like playing 3D chess; you have to get all the layers and levels correct."

Clear inferno operator Ben Murray does his best to translate the technique into layman's terms. First of all, he says the actors had to rip off real masks because the hair movement would have been virtually impossible to replicaterealistically on the computer. However, Clear did use CG in the six frames prior to each mask-pull to warp and crumple the face before it was completely ripped off.

Many layers were shot to accurately composite those heads. In "Grannies", a locked-off camera captured the original shots of the actors. Heads of the underlying personalities were shot on a green screen and then composited onto the body. Additionally, the granny's inside back collar was shot and placed behind each changing head. Each shot represented a different layer.

"The premise of how we got there was a bit like Sleepy Hollow," Murray says. "We made the grannies headless, so we have elements of grannies with no heads moving around, and we put contactshadows in."

Another element was the armmovement. The granny's arm had to match up with each mask of the actors. This meant filming the 78-year-old actress several times to match each hand-to-maskcontact exactly.

Clear then added in a plate of the background, and a plate of driving rain imposed over the whole scene. Toss in a slight camera weave and the fact that the spots were shot on 35mm at 50 frames per second (fps) and interlaced at 25 fps to achieve a verité look, and you start to get what Pope means when he refers to the process as a chess match.

Post-producer Steve Garrad points out that absolute precision was required because, unlike many projects, this one couldn't be fixed in post. "It has to be shot exactly. If a face lineup doesn't match, it won't work; it'll just look fake."

Total post time for the second pool came in at six weeks and Pope says the 11-day shoot went smoothly thanks to extensive pre-vis time. But, "because it's the BBC", Garrad declines to comment on budget - stating only that, by commercial standards, it wasn't huge but was "still a decent amount of money".

As for Pope, he's pleased that the team was able to bring a clever concept to the next level. By contrasting the large, sweeping and musical, with the simple, hand-held and sound designed, he feels they have succeeded.

"It's quite rare when you can do something surprising and come back and surprise again."

WEBFILES:
BBC> http://www.bbc.co.uk
Clear> http://www.clear.ltd.uk
Cowboy Films> http://www.cowboyfilms.co.uk
Duckworth Finn> http://www.dfgw.com