Without Remorse is a thriller novel published in 1993 by Tom Clancy and is a part of the Jack Ryan universe series. While not the first novel of the series to be published, it is first in plot chronology. The main setting of the book is set during the Vietnam War, in the American city of Baltimore. The book focuses on the development of one of Clancy's recurring characters, John Kelly/John Clark, while providing the character some back-story. The book serves to give a history of Kelly's life, and explains how he becomes John Clark.