Think you've seen it all in advertising? Then wait for this one. 'Swap', Levi's latest ad to push the new Levi's Type 1s, features mutant mice people. It involved a serious session of real mice-casting before the production could go ahead.

But it was this decision to use real mice, as opposed to CGI, models or animation which clinched the deal for director Michel Gondry, according to the creative team Steve Rutherford and David Chalu.

And a bizarre script such as this, which features the mice-people terrorising the inhabitants of Los Angeles, was perfectly suited to the innovative Gondry.

Believe it or not, live mice were screen-tested for the mice-hybrid parts and were selected if their characteristics were similar to the human models - not a huge compliment for the actors.

The director used all kinds of crafty techniques to get the mice to perform from putting honey on sticks to lure them towards the camera to waving the stick up and down to get the rodents to jump about. Gondry then had to slow the camera to catch the mice in slow motion so that the viewer could see every fine detail from whiskers to eye's twitching.

In a nice departure for glossy big-budget brands, the entire commercial was shot on video, giving it an underground feel.

Not surprisingly, a huge sum was spent in post-production with the Buf boys working their magic to achieve this unprecedented feat. Even on the shoot, concerns were voiced by special-effects experts as to its feasibility. In fact, a significant proportion of the overall production budget was put into the post production, where the head actions of the mice were digitally crafted onto the models. This took over four months to complete.

Nothing was overlooked in the management of this production which involved a crew of 140, including a minder for the handpicked mice flown in from LA to New York for a special mice shoot. In fact, the celebrity mice were even groomed before they were captured on camera.

The cutting-edge music was created especially for the ad, and was written and produced by Massive Attack's Nellee Hooper.

Continuing it's pioneering spirit, BBH is to release a music video - one of the first agencies to do so - to accompany the track that appears in the ad. The promo will feature the same mice characters from the commercial and was produced in-house at the agency.