"Twelve-year-olds Lizzie Sancho and Dido Belle are from different worlds - Lizzie lives in Westminster in her dad's tea shop, while Belle is an heiress being brought up by her aunt and uncle at grand Kenwood House - but they both share a love of solving mysteries. And when their eyes meet in the audience of the Drury Lane theatre one night, both girls are sure they've seen something suspicious on stage. Lizzie and Belle soon find themselves on the trail of a mystery - and becoming best friends. But can they work out what's going on in time to prevent a murder?"--Publisher's description.