I enjoyed this movie, for the same reasons as previous commenters did. I also liked the absence of hackneyed plot devices, such as the McDormand character being taken off the case but solving it anyway, or a turf war between the local police and the FBI.

However, I notice that the opening credits say that the story is true, while the closing credits say that it is entirely fictional. For a while I thought that it was a true story, then I realized that the murder of three people, including a police officer, would be taken very seriously. Instead of the case being given to one uniformed officer, a team of homicide detectives would descend on the scene.

It would have been better if the makers of the movie had been straightforward about whether the movie is true.