Grandfather and his spunky dog Roo set out on another silly and over-the-top adventure, which this time takes these two unlikely explorers from England and across the United States in search of Roo’s (in)famous grandfather, Old Blue. In their travels, which are characterized by calamities and last-minute escapes, the pair find themselves roped into such humorous situations as being stuck on a Greyhound bus with a pack of misbehaving greyhounds and being trapped in a town overrun by outlaw wild horses. Readers familiar with Horse’s work will recognize familiar elements and themes, including the duo’s uncanny ability to escape hair-raising situations and the cast of offbeat anthropomorphized animals that they meet along the way. As in the other Grandfather and Roo tales, this text is a series of bite-sized letters addressed to Grandfather’s gender-neutral grandchild, a technique that makes the whole both palatable and approachable for transitioning independent readers. Imaginative and fun. (Fantasy. 6-8)