 The word "gallowglass" means servant, or one indebted to another. This is the story of a young man who feels such indebtedness to another young man after he is saved from committing suicide by jumping in front of an oncoming train. So strong is his sense of gratitude that he follows his  savior  even to the kidnaping of a wealthy woman. But there are ulterior motives to the kidnaping, complicating it with other details that intertwine and make for a typical British murder mystery.