At 23 stone, party-loving Carley Brookes loves instant food and refuses to do any exercise. 22-stone Darran Mansfield has been told by his doctor that he is on the brink of full-blown diabetes, yet he's too stubborn to change his unhealthy ways. So will witnessing the effects of living an ultra-lazy lifestyle in Kuwait and meeting a 51-stone recluse have a big enough impact to get the Brits to radically turn their lives around?