(From the publisher):
Holly could hear the blood pounding in her ears. She looked cautiously round the corner into the hall. It was deserted. 'Come on, she whispered, 'It's our only chance.' Suddenly there came an ominous sound: a key turning in a lock. Holly ran for the doors, but she was too late. The cartetaker had locked them in with the two dangeerous men.
Original title: Secret Clues
Genre: Fiction→ Children & Young Adult→ Mystery