The first book-length study of Horace Walpole’s scandalous The Mysterious Mother, including critical essays, an abridged script, and a facsimile edition Horace Walpole’s five-act tragedy The Mysterious Mother (1768), a sensational tale of incest and intrigue, was initially circulated only among the author’s friends. Walpole never permitted it to be performed during his lifetime except as a private theatrical. He described his play as a “delicious entertainment for the closet” and claimed that he “did not think it would do for the stage.” Yet the essays in this volume trace a history of private readings, amateur theatricals, and even early public performances, demonstrating that the play was read and performed more than Walpole’s protests suggest. Exploring a wide variety of topics—including the play’s crypto-Catholicism, its treatments of incest, guilt, motherhood, orphans, and scientific spectacle, and the complex relations between print and performance—the essays demonstrate the rich relevance of The Mysterious Mother to current critical discussions. The volume includes the proceedings of a mini-conference hosted at Yale University in 2018 on the occasion of a staged reading of the play. Also included are the director’s reflections, an abridged script, a facsimile of Walpole’s own copy of the full-length play, and reproductions of the illustrations he commissioned from Lady Diana Beauclerk.