"The Mystery of the Strange Bundle" is the tenth instalment in Enid Blyton's popular series, The Five Find-Outers. In this exciting tale, the Find-Outers, who have been recovering from the flu during their Christmas holiday, stumble upon a peculiar robbery. Despite nothing appearing to be missing from Mr. Fellows' house, he behaves strangely by running out in the night and discarding a mysterious bundle into the river. Will the Five Find-Outers unravel the enigma of the strange bundle and uncover the secrets hidden within?