In the latest spot, stars including Winslet, Zoe Ball, Liam Neeson and Ian Wright will appear farting. Monkey, the former mascot of ITV Digital, will also appear. Last year, he was banned from fronting the Comic Relief campaign by ITV Digital's administrators.
The 40-second spot was created by Abbott Mead Vickers BBDO and promotes Walkers' limited-edition baked bean flavour.
Walkers stalwart Gary Lineker appears in the ad in his usual role as would-be Walkers thief. However, he is thwarted in every attempt to separate the stars from their snacks, as all of them inadvertently repel him with a fart just as he is sneaking up to rob them.
Kate Winslet farts in front of her television; Zoe Ball bubbles in her bath; and Ian Wright does the deed in a men's locker room.
The ad debuts this evening during ITV1's 'Coronation Street' and will air up until Comic Relief's Red Nose Day on March 14.
Winslet has appeared naked on screen more than once but said of her performance: "I thought it would be a lot easier with just a handful of people around, but it was worse -- I just had a fit of the giggles and couldn't control myself. Oh well, it's all in a good cause."
Walkers is donating 1p from every packet of baked beans-flavoured crisps and Monster Munch and 5p from baked bean multi-packs to Comic Relief. The promotion will also see Walkers give away 5m whoopee cushions in the UK.
Comic Relief has raised a total of £250m for charities targeting poverty in Africa and the UK. Walkers has already agreed a £1m donation, besides the funds raised by the baked beans-flavour promotion.
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