Sian has been raised on a farm with her mom. Her life is pleasant chaos, filled with lots of chores, lovely animals, especially her beautiful pony Marnie, and several rescue horses, but she's in need of a friend. Then Jess moves in next door. Jess has had a life of luxury: a father who will give her anything, servants who are like family, and now a new house in the country and a new dream horse, Tag. The best of everything! Yet she, too, has a problem. Something is terribly wrong with Tag. He seems miserable and lonely. Sian wants to help, but there's a catch; their parents don't get along and have forbidden the girls from seeing each other. The answer to both girls' problems will launch them into all sorts of trouble!