Henry Naylor's new show for ITV, Headcases, is a very mixed bag.

The show's promoted as Spitting Image MkII, but it doesn't look like there are any artists on board who can touch the inestimable Peter Fluck and Roger Law, or even the team who worked on 2D TV. The Piers Morgan caricature is at the forefront of the show's publicity material, yet more closely resembles Stephen Fry; attempts at certain political figures like Nicholas Sarkozy and Nick Clegg, and even obvious targets like Tony Blair, are astonishingly poor. And apart from the fact that many of the likenesses are wide of the mark and the scripts are equally in need of the red pen, the real reason the show leaves a weird impression is its neither-fish-nor-fowl execution. The faces have been caricatured in a conventional pencil and paper manner before digital modelling. But the bodies are more often than not animated using cutting edge motion capture techniques. In other words, although the characters LOOK like cartoons, they don't MOVE like cartoons. As recent feature film experiments with the technology have shown (Happy Feet, Beowulf) mo cap works well when portraying the extraordinary and fantastic, but when used to sell the idea of someone just strolling across a room, it somehow draws attention to its artifice and thereby pulls the audience out of the narrative. Watch the spoof of Madonna of the David Cameron press conference in episode one of Headcases and you'll see exactly what I mean.

Aside from Robert Zemekis, the world's leading proponent of mo cap is probably Peter Jackson. Having cut his teeth on Gollum and tweaked the tech on Kong, he's in the midst of filming The Adventures of Tin-Tin entirely on mo cap stages. However, a very great deal of the former two "performances" were completed by animators; enhancing, emphasising, exaggerating and at times entirely ignoring and replacing the physical movements of actor Andy Serkis. Of course, on the third film Serkis will be playing a salty sailor, not a giant ape or Ring-wrecked Hobbit. It remains to be seen whether a cgi Capt. Haddock will require the touch of a true animator's talents in order to succeed and will depend on whether the film's designers will attempt to replicate Hergé's clear-line aesthetic or just use the kind of hollow-eyed zombies that populate The Polar Express.

For a lot more on the importance of funny, exaggerated movement in animation, read John "everything modern is soulless shit" Kricfalusi's hugely absorbing, hyper-opinionated blog.