Books about Mystery fiction (sorted alphabetically)
- official chaperon Natalie Sumner Lincoln
- Pagan Madonna Harold MacGrath
- Pam and the Countess E. E. Cowper
- Patsy Carroll Under Southern Skies Josephine Chase
- Patty and Azalea Carolyn Wells
- Pauper of Park Lane William Le Queux
- Peggy Parsons at Prep School Annabel Sharp
- Pointing Man: A Burmese Mystery Marjorie Douie
- Poor Wise Man Mary Roberts Rinehart
- Poppy Ott's pedigreed pickles Leo Edwards
- Primadonna F. Marion Crawford
- Primus Curse Bill Wesley
- Professor's Mystery Wells Hastings and Brian Hooker
- Putnam Hall Cadets; or, Good Times in School and Out Edward Stratemeyer
- quest for the rose of Sharon Burton Egbert Stevenson
- Raffles: Further Adventures of the Amateur Cracksman E. W. Hornung
- Rambler Club Afloat W. Crispin Sheppard
- Rambler Club's Winter Camp W. Crispin Sheppard
- Red Lady Katharine Newlin Burt
- Red Pirogue: A Tale of Adventure in the Canadian Wilds Theodore Goodridge Roberts
- Red Symbol John Ironside
- Red Widow; or, The Death-Dealers of London William Le Queux
- Red Window Fergus Hume
- Rest Hollow Mystery Rebecca N. Porter
- Return of Dr. Fu-Manchu Sax Rohmer