Books about Detective and mystery stories (sorted alphabetically)
- Meredith Mystery Natalie Sumner Lincoln
- Merriweather Girls in Quest of Treasure Lizette M. Edholm
- Messengers of Evil Pierre Souvestre and Marcel Allain
- Middle of Things J. S. Fletcher
- Middle Temple Murder J. S. Fletcher
- Middle Temple Murder J. S. Fletcher
- Midnight Octavus Roy Cohen
- Midnight Guest: A Detective Story Fred M. White
- Miljoonan dollarin timantti (Finnish) J. S. Fletcher
- Millbank Case: A Maine Mystery of To-day George Dyre Eldridge
- Millionaire Baby Anna Katharine Green
- Millionaire Baby Anna Katharine Green
- Millionaire Mystery Fergus Hume
- Millionaire of Yesterday E. Phillips Oppenheim
- Million Dollar Mystery Harold MacGrath and F. Lonergan
- Million-Dollar Suitcase Alice MacGowan and Perry Newberry
- Mill Mystery Anna Katharine Green
- Minute Mysteries [Detectograms] H. A. Ripley
- Mischief-Maker E. Phillips Oppenheim
- Missing Will Agatha Christie
- Missioner E. Phillips Oppenheim
- Mission of Poubalov Frederick R. Burton
- Mississippi Outlaws and the Detectives Allan Pinkerton
- Miss Maitland, Private Secretary Geraldine Bonner
- Miss Mephistopheles: A Novel Fergus Hume