Bert's little sister knows that he loves to bring home pets and hide them in his room, and her curiosity about what is going on in there has been building and building. Finally she simply cannot wait any longer to check it out for herself. Inside, she discovers a zoo-worthy collection of animals tucked into every nook and cranny. But after she gets them out and about, can she undo the chaos and put everyone back in their proper places before Bert comes home?

Playful illustrations by Tracey Campbell Pearson offer a bright and funny new interpretation of Ted Hughes's classic poem.