Ina, Tine, and Alex were excited to join the owner of the Horse Farm, Mr. Book, on an afternoon ride to check the perimeter of the farm for breaks in the fences. They were alarmed when they heard loud voices and muffled shouting in the distance. At the edge of the forest, they came upon a scene that broke their hearts. Because of the actions of an ignorant woman, a very young fawn was in danger of starving to death. Can Mr. Book and the girls do anything to save the young deer, or will it be doomed to suffer?

It's an exciting week at the horse farm! Alex's mare Lilian is going to be a mother, and everyone is ecstatic about the new arrival. Though the news is happy, Alex, Tine, and Ina are worried about the first-time mom. They want to make sure everything is just perfect for the birth of the little foal, so they decide to keep watch over Lilian as she goes into labor. But when complications arise during the delivery, will the girls be able to get help to the mare before it's too late?

The summer riding festival is coming to the Horse Farm, and it is sure to be an important event for close friends, Ina and Tine to showcase their equestrian skills. The only problem is that the girls need a third rider for their plan to take shape, and the snooty mean girls, Bettina and Sarah seem to be their only option. That is until a new rider Alexandra, and her horse Lilian show up at the farm. Have Ina and Tine finally found their third Musketeer, or will Bettina and Sarah chase Alex away with their cruel antics?

Though Bubi, a white Welsh pony, has only lived at the horse farm for a few weeks, he is already causing several problems for friends Tine, Ina, and Alex. While the messes he makes are annoying to clean up, and his gluttonous appetite can be a bit of a bother, the girls would be happy to ignore his flaws, if only they could find him. The pony seems skilled at disappearing, and locating him may be the least of their problems, if they cannot figure out how he keeps escaping.

With Lilian still caring for her young foul, Alex borrows the farm's horse Gilda, whenever she goes riding. One afternoon, Tine, Ina, and Alex take the horses to the ruins of a nearby castle. The girls get caught in a storm that spooks all the horses, but sends the skittish Gilda into a panic. When she manages to escape, they are sick with worry about the borrowed horse. After all, she is all alone, in unfamiliar surroundings, in the middle of a terrible thunderstorm.

Something is amiss at the horse farm! During the night, someone broke in completely undetected and escaped with two very expensive saddles. The thief left no trace of a forced entry, and no tracks that anyone can find. Since Tine's cousin Gerrit is spending the day with Tine, Ina, and Alex, he offers to help investigate the pilfered items. Can the children locate the items before the thief sells them, or will they find themselves trapped in dangerous situation?