Felicity is a twelve-year-old with too many problems to count but if she discovers an animal that everyone else thinks is extinct, or never even existed in the first place, she will be rich and famous and her worries will be over. Together with her new friend, nine-year-old Simon, her uncle and dog, she goes to the highest and most dangerous mountains in the world to find the most mysterious animal of them all. But someone – or something – doesn’t want them to succeed.