Eight fat dogs and their equally overweight owners take on a joint diet and exercise regime in the ultimate weight loss contest. The pairs are introduced to a new piece of gym kit at the Fat Dog Fitness Camp - the doggie treadmill. But for the neurotic bulldog and overweight labrador, a moving floor is terrifying. The weigh-off is tough for everyone - after six weeks of dieting, the contestants are starting to falter. The two losing pairs must go head to head on the doggie treadmill challenge.