Murder in Thrall: A Doyle & Acton mystery Revised edition

A trainer has been murdered at a London racecourse, and in quick succession, two potential witnesses also lie dead. Rookie detective Kathleen Doyle has been assigned to be Chief Inspector Acton's support officer on the cases, but thus far, they've little to work with; the killer appears to be a professional, but the gruesome crime scenes are not the work of a professional killer. Indeed, there seems to be an almost pathological rage motivating these murders, which makes Doyle very uneasy, especially since she'd the sense that the killer was turning his focus upon her. . . The first book in the Doyle & Acton Scotland Yard series, as revised by the author in 2020