Like Jack the Ripper, circumstantial evidence, obsessive conjecture and legend surround the Zodiac Killer. It’s these stories rather than that of the murders themselves that David Fincher (Se7en, Fight Club) tells in Zodiac. It’s a film about the people whose lives were turned upside down by their desperate need for an answer during a time of uncertainty and disillusionment.

It’s a typically slick (albeit less outwardly stylistic) film from Fincher, but it’s also a measured, confident procedural that is gripping from start to finish (the director’s cut adds five unnoticeable minutes to the 158-minute running time). Even when it starts to lose steam toward the end as the structure breaks down, it’s been such a fun ride that you want to forgive it.

Making up the excellent cast are: Jake Gyllenhaal, as the obsessive code-breaking cartoonist Robert Graysmith (author of several Zodiac books), Robert Downey Jr. in another of a line of wholly engaging performances, Marc Ruffalo, Brian Cox, Anthony Edwards and Chloë Sevigny.

Basing the script on Graysmith’s books, Fincher and screenwriter James Vanderbilt also did extensive first-hand research, which is explained in the making-of doc. Also included are video interviews with real life figures involved with the case, including an investigation into the lead suspect, Arthur Leigh Allen.

The always-interesting Fincher has a commentary track, along with one by the cast. Also included is a featurette on Fincher’s subtle use of CGI to bring to life 1970s San Francisco.

Grade: A-

Zodiac – The Director’s Cut is currently available.