Deputy Assistant Commissioner Charlie Hillian was killed on the night of his retirement party. Hillian was once a senior officer at the University of Oxford, but was actually Morse's superior. He also wrote a book about his most unforgettable case, including a book about the unresolved death of an 8-year-old girl about 18 years ago. The suspect in the case, Frederick Redpath, passed away on the day of his death at Hillian's home, and the chapter in the manuscript was missing. However, there are other suspects, including Xilian's ghost writer, who will now receive all royalties from the book; A handyman working on this property; And Radpas' daughter, who knows the little girl who was killed many years ago. Morse clashed with his colleague DCI Dawson, who was one of Hillian's disciples, and they re investigated the death of the little girl.