Orphaned Bo is invited to visit his estranged relatives in the Mojave dessert. A generations-old feud involving a legendary “black gold” mine has kept the Gammages and Martinkas apart. Now, Bo isn’t sure if his invitation is an honest one, or just more family intrigue. His quirky, same-age cousin “Mzzz Mad,” a 12-year-old who drives her own truck, just makes things worse, until they both get caught up in a very real and dangerous mystery. Fleischman is at his best here—his characters and setting come to life instantly, in a lightning-quick plot that is nevertheless rich with tension. He pulls off both slapstick humor and heartfelt drama in a genuine and appealing way. Walking the line expertly between tall-tale and believability, he will delight readers with his “Author’s Secrets” note at the end, which not only lends credence to his story, but might just inspire a few young would-be writers. The books’ short length and quick pace make this a perfect choice for older, struggling readers; but don’t pass on this because it looks easy—this is pure good reading. (Fiction. 8-14)