Book 4 in the Cass and the Bubble Street Gang series! Cass, Lex and Nicholas investigate crimes, solve mysteries and have brilliant adventures. They've even got their own secret clubhouse. Cass is ecstatic. Mr McCall's partner is starting a Scarecrow Festival at the McCall mansion, and it includes an all-day, mind-boggling scavenger hunt. Throughout the mansion, gardens and adjoining fields, Cass and the gang will test their wits against other scavenging teams, including Nathan Wall and the NaSaJi Club (Nathan, Sasha and Jim). But Cass isn't worried. She knows she'll win; she has detecting in her blood. But, the NaSaJi Club sabotage the Bubble Street Gang. Then, Mr Freebs has paired Cass with Nathan for a project to spruce up the gardens of a nursing home. When an elderly woman called Carmella loses her locket, Cass must put her detective skills to the test to solve the mystery of golden locket.