The second children's murder mystery from number-one-bestselling author of The Appeal, Janice Hallett, perfect for fans of Robin Stevens and Rhian Tracey.

Imagine an old museum with more secrets than anyone could ever guess. A school trip that ends in murder. A crime unsolved for decades. . . But who did it?

Now, Ava and Luke are on the case, following the clues left in a new box of murders. Using School workbooks, museum records, secret recordings and letters the siblings start to unravel the mystery of a body in the basement. But can they discover what really happened . . . before the killer strikes again?