PD (Penelope Delores, when she's in trouble) was enjoying an afternoon with her grandparents, when a most terrible crime was committed, right under her nose!

The first book focuses on the dreaded recorder, a staple in Australian schools, which PD has just discovered. She starts a Christmas band with her recorder, and dog Scooter accompanying on the barks. PD's grandparents are caring for her during the school holidays and doing their annual clean up. PD finds her grandparent's old trilby coat and decides to start her own Detective Agency. When the recorder disappears, PD must use her sleuthing skills to uncover the culprit…and no one is above suspicion.