Hairy Bikers Si and Dave embark on a campaign to lose two-and-a-half stones in three months. They join forces with a group of overweight foodies looking to shed pounds themselves.

Hairy Bikers Si and Dave tackle a slimline cooked breakfast and a roast chicken family dinner; after swapping their famous motorcycles for bicycles, a final challenge awaits.

Si and Dave try to redesign the pie, one of the nation's favourite comfort foods and one of their fellow big eaters' favourite treat. The duo also learn that though their diet is working, they need to reduce their calorie intake to an even lower.

Dave and Si must reinvent the indulgent party treats they adore and celebrate their new svelte frames with their families and friends.