It is way too long even with the quality support casting on show. However, Cruise plays a part that requires him to do some acting for a change so it does contain some light entertainment.
It works best on Duvall's side of the screenplay (with support from the likes of veteran Kenneth McMillan), particularly when investigating the crime. The rest is rather flat.
I'm not a fan of a dramatisation of real–life events in lieu of a documentary but this one is sincere and respectful in its telling. The production values are top notch and the cast oozes talent even in the smaller supporting roles.