Although an accomplished academic, James is best remembered for his antiquarian ghost stories, which he famously read aloud to friends each Christmas Eve. His tales broke with traditional Gothic conventions, setting supernatural horror in ordinary, contemporary settings—sleepy villages, libraries, and country houses—where scholarly curiosity often awakens malevolent forces.
His major collections include Ghost Stories of an Antiquary (1904), More Ghost Stories of an Antiquary (1911), A Thin Ghost and Others (1919), and A Warning to the Curious and Other Ghost Stories (1925). Celebrated works such as "Oh, Whistle, and I'll Come to You, My Lad" and "Casting the Runes" exemplify his signature style of understated dread. His "pleasant terror" technique profoundly influenced later writers, including H. P. Lovecraft, and continues to inspire adaptations in film, television, and radio.