A TV ad featuring 225 Creme Eggs being 'gooed' in mousetraps marks the finale of Cadbury's multimillion-pound campaign in the runup to Easter.

The TV ad, which breaks tonight, tested the mettle of ad agency Publicis London, requiring 23 hours to set up but just nine seconds to shoot.

The mousetrap extravaganza forms the finale of 20 short ads that began on January 1, the earliest Cadbury has ever started a Creme Egg campaign, with each commercial focusing on a different way to get the white and yellow fondant "goo" out of one of the chocolate eggs.

Each of the 20 ads has featured Creme Eggs being split open in ever more elaborate ways with objects including a hammer, a picture and ghetto blaster.

The tongue-in-cheek ad campaign uses the strapline "Here today, goo tomorrow".

Publicis's campaign that eschewed the usual method of developing one or two full-length TV commercials and instead opted for a viral internetyle series of short clips up to 15 seconds long.

"I can't remember a campaign that Cadbury has done that has used shorter time length ads," said the Cadbury UK marketing director, Philip Rumbol.

"In many respects the clip length of the ads really has an online ethos at its heart. The target market is 16- to 24 year-olds and we need to be about interest and variety, rather than just creating one or two ads that you keep banging."

Cadbury is now planning to edit a version of the finale mousetrap ad in slow motion, with a symphonic soundtrack, to be released online.

The TV campaign has been supported by outdoor and digital advertising and saw a departure from 23 years of using the "How do you eat yours?" concept for Creme Egg.

Cadbury has also involved Creme Egg in a stunt within Bebo's online drama KateModern that saw one of the show's characters, playing a PR girl, attempt to manage the brand with a comic egg free-for-all in Leicester Square.