The mystery of the burnt cottage. Originally published: London: Methuen, 1943
The mystery of the disappearing cat. Originally published: London: Methuen, 1944
The mystery of the secret room. Originally published: London: Methuen, 1942.
The mystery series. Volume 1 by Enid Blyton. ISBN 9781405275620. Published by Egmont in 2015. Publication and catalogue information, links to buy online and reader comments.