It's a wonderful movie. Historic accuracy is stunning, the details are perfect - unto the point of you have to admire the way the characters wear their coats.
It is also a heartbreaking story about treason of friendship and fate and resignation to death, served by excellent actors. John Thaw delivers an outstanding performance, Paul Darrow is a heartbreaking Doughtie, noble and dignified all along. Darrow plays the part with a talent I had never seen him display before, in a subdued, soberly tragic way . The painful destruction of their friendship is actually at the core of the movie.
Really, you have to wonder why we haven't been granted the pleasure of watching this movie on DVD, since it doesn't seem to be available anywhere.