The Mystery of Tally-Ho Cottage is a 1954 novel written by Enid Blyton and illustrated by Treyer Evans. It is the twelfth book in the Five Find-Outers series.
The mystery begins when the newspapers report that a valuable picture has been stolen from an art gallery. The police know the identity of the thieves—the Lorenzos of Tally-Ho Cottage. The Lorenzos eluded capture, but had to leave their poodle, Poppet, at Tally-Ho, though they had engaged an elderly couple, the Larkins, to take care of it. But the Lorenzos wanted to take their poodle with them.
Ern, who was living near Tally-Ho, kept a watch on the grounds to see when the Lorenzos would arrive. He heard noises in the night but slept. In the morning, he informed the Find-Outers about the noises, which he thought were like an airplane or car or motorboat. Upon investigation, the Find-Outers find that the Lorenzos did in deed arrived in a motorboat. Upon further investigation, the Find-Outers find that the Larkins had left when the Lorenzos arrived and the Lorenzos are disguised as Larkins.
The Lorenzos are then arrested. The stolen artwork is found stitched inside a rug of Poppet the poodle.