Well-told, well-directed and well-paced realistic and immersive true crime movie but one wonders why an unresolved case was chosen. These kind of cases are perfect subjects for documentaries, and you could convey a similar message. Even though, the movie tells us from the beginning that this case is unresolved, the audience still feels disappointed in the end.
For my taste, the movie was a little too much focused on the subplots outside of the case, which also were nice subplots - but again it did not fit that well to the genre. This brings us to the great weakness of the movie: it plays against audience expectations; disappoints most crime genre fans. It could be the greatest story but if you break basic rules and dont keep your promise for the genre, it will be an uphill battle. With a different case chosen, this had the potential for a great movie.