The Mystery of the Haunted Cottage

 The Mystery of the Haunted Cottage  was a book in the Troubleseekers series by Annette Billingsley. In the story, a group of child detectives, the Troubleseekers, investigated strange lights in the woods by a cottage. Characters in the book were Humphrey, Jo, Gertie, Simon, Fatty, Mrs. O'Grady, and Cotterill. A Ch'otterai brought the book to life when Martha Jones and the Tenth Doctor visited his planet, as this was the book that affected Martha Jones the most. (PROSE: The Mystery of the Haunted Cottage)