Heather's best friend is a girl called Isla, who lives with her dad on a farm in Scotland. Their idyllic life together is shattered when a thunderstorm destroys the farm and forces Isla's dad to sell up and move to London - leaving Isla and Heather miles apart and utterly miserable.
Then fate intervenes, turning Heather from an everyday pig into a national celebrity, and catapulting her to fame, fortune and, most excitingly of all. . .London.
Armed only with her own pig-headedness, Heather embarks on a quest to track down her best friend. After all, how many girls with freckles can there be in London?