Uncle Hoole wants to study the S'krrr--a race of creatures that look like giant bugs. While Hoole works, Zak and Tash visit the S'krrr's huge garden--it's the most beautiful place they have ever seen. It's also full of very strange creatures. When a batlike shreev swoops down at Zak, he panics and accidentally kills it. Suddenly, the garden is overrun by big beetles. When Zak wakes up in the middle of the night covered with creepy crawly bugs, he's terrified. Did Zak upset the garden's delicate ecological balance by killing the shreev? Or is something far more sinister at work?