Saddle up for a week in pony paradise! At Sunnyside Stables, each girl gets her own pony to look after and ride for a week. Millie and her pony Tally have been a team for years, so she's heartbroken when she gets too big for him. Now Tally must join the other Pony Camp ponies, and Millie has to try out new pony Magic. But Millie is determined to keep Tally and comes up with a risky plan. Will Millie land herself in big trouble?