ITV Headcases: A new cast of computer-generated characters is satirising the media

Headcases, (ITV1 Sundays 10pm), is the first satirical sketch show with a cast of entirely computer-generated characters. Billed as a Spitting Image for the 21st century, the animated programme casts its net widely, poking fun at everyone from Gordon Brown to Heather Mills. It received a reasonably warm critical reception after its first episode aired three weeks ago, and has already reported encouraging audience figures of around four million.

Henry Naylor, the creator and series director of Headcases, was also a lead writer on Spitting Image for three series. Although he still remembers the iconic puppets of his old programme with great fondness, he believes that only computer animation is versatile enough to hold the attention of modern audiences who are again longing for a sharp dose of irreverent satire.

"I think the puppeting tradition of Spitting Image was great," he says, "but it's not right for this age. When I first saw Toy Story at the cinema, I thought: that's the way it's going to go, that's what satire is going to evolve into. Spitting Image had a ramshackle feel – that was part of its charm. But it belongs to an older tradition, and puppets are quite limited: you're restricted in terms of what sets you can use, and in the movements that the characters can go through. We've been sending up President Sarkozy as a medallion-wearing disco dancer – you couldn't do that with a puppet."

Although Naylor admits that his new programme has the same aim as Spitting Image at its heart – to make political figures accessible to the public through satire – he also wants it to be a lot more ambitious and wide ranging in its scope. In one sketch, the ageing Hollywood actors Bruce Willis and Sylvester Stallone are tortured by a medusa-like Heather Mills. Cinematic sketches like this one have to be prepared months ahead of schedule, but modern animation technology allows a good portion of the show to be produced the week before going on air. This means that anyone in the public eye is a potential target, including media figures.

"We live in a very personality based culture now," says Naylor, "and as a result people know much more about public figures than they ever did before. When even David Cameron is inviting cameras into his home, you can see there's been a major change in the culture – you couldn't dream of Thatcher doing that.

"In an age with a real PR culture and a strong sense that people are being lied to all the time, the public needs a redress against certain figures: I think it's important that there's a vehicle for this, not just to slag them off, but to hint at the truth."