I had seen the Tony Curtis movie, and had also learned that DeSalvo may not have been responsible for all the killings, but that was all I really knew about the case, so this movie filled in a lot of the gaps, and while it featured a lot of interesting information, I did wonder why the epilogue did not include anything about the person of interest named Dempsey, who I then had to search online to find out that he was a fictionalized character based on a man named Charles Terry, who was suspected of being the original Boston Strangler.
I did expect more of a sense of urgency; the film just seemed to ramble along on one flat note, whereas films like this tend to, via very typical means of direction, acting, soundtrack, camera angles, etc., produce more tension and suspense, even if only on the part of the characters in the story. There was just no excitement here or any feeling of accomplishment, either from Carrie or Keira, and I have to note that Keira was strangely stiff. Her face never seemed to change expression, and while I didn't mind her accent at all, not expecting the characters to all have the typical Bah-ston accent, I was more put off by her total lack of affect, and I really hope it was simply due to some medical procedure like Botox and not that she is just losing her touch. In fact, it was strange to see more animation in the still photos shown in the epilogue of the actual woman she played..
So while the film has an interesting and informative storlyline, it just feels totally flat and uninvolving, and you will really have to make an effort to stay focused..