The Colonel is missing, and Aunt Emily is sad and severe again. But what does the Colonel's disappearance have to do with two notorious toy thieves? Daniel sets to work to find out. With the help of some escaped zoo animals, can Aunt Severe and Daniel track down the toy thieves and bring the Colonel home again?

When Daniel's explorer parents vanish, he is forced to live with his strict and rather strange Aunt Severe. And his problems only increase when Daniel finds four lost dragons hiding in her garden. But before he can help, three of them are captured by evil Gotcha Grabber and thrown into a zoo. And so, with the help of Dud - the shy and clumsy fourth dragon - Daniel sets out to rescue them.