Pirates, family, and the truth about Mo's Upstream Mother collide in the conclusion to the Newbery Honor and New York Times bestselling Three Times Lucky When the Colonel and Miss Lana share the clues about Mo's watery origins that they've been saving, it seems the time is finally right for the Desperado Detectives (aka Mo, Dale, and Harm) to tackle the mystery of Mo's Upstream Mother. It's the scariest case Mo's had by far. But before they can get started, Mayor Little's mean mother hires them to hunt in her attic for clues to Blackbeard's treasure, which could be buried right in Tupelo Landing. Turns out, the Desperados aren't the only ones looking. A professional treasure hunter named Gabe has come to town with Harm's estranged mother—and soon the race is on, even though the treasure's rumored to be cursed. As centuries- and decades-old secrets are dragged into the light, there isn't a single person in Tupelo Landing quite prepared for all that they uncover. Especially Mo. The fourth and last book in the Mo & Dale Mystery series and the long-awaited conclusion to Three Times Lucky, The Law of Finders Keepers is a heartbreaking, heartwarming, honest, and hilarious adventure that you can read right after you finish Three Times Lucky.