Izzy isn't looking forward to spending her school holidays on her aunt and uncle's farm. But when she finds out that Jessie - a fluffy Old English sheepdog puppy from Battersea Dogs & Cats Home - will be joining them too, her summer suddenly starts looking up! Izzy and Jessie get up to all sorts of mischief in the countryside - including stowing away on a neighbouring farmer's tractor! But when Izzy's uncle's prized flock of sheep wander off, it's time to put Jessie's sheepdog abilities to the test. Will Izzy and Jessie be able to track down the missing flock?