Based on real events, Zodiac tells the story of a series of unsolved murders which took place in San Francisco in the 1960s and 1970s. The serial killer, know as the titular Zodiac, taunted the police with letters and ciphers sent to newspapers, but despite long investigation into the case, and several possible suspects, the true identity of the killer is still unknown to this day.

Zodiac begins in 1969 and spans all the way through to 1991. While is historically correct in terms of the investigation and the prime suspect Arthur Leigh Allen, the substantial time frame offers up the films most problematic element. Choosing to highlight specific moments from the investigation, some of which happen years apart from one another, can make the film difficult to follow and leave the viewer feeling as though something is being missed out. And considering it spans 22 years, the characters appear ageless in appearance. One needs the name of their surgeons... Anyway, all the skipping ahead years at a time, means an awful lot is crammed in and leaves the run time at a hefty 157 minutes. A more concentrated study on a more definite event or part of the investigation perhaps would have made more engaging viewing. Instead too much, sadly equals too little.

Perhaps my view would be different if one had read Graysmith's book beforehand. However, one didn't, so it is not.

Graysmith's viewpoint from the San Francisco Chronicle is great however, and does offer something different than usual to the crime genre. Jake Gyllenhaal is fantastic as Graysmith, the man to becomes obsessed with the Zodiac, sacrificing his marriage and children to the cause. All consumed by solving the case, Gyllenhaal portrays this convincingly and empathetically and is surely the best thing in Zodiac, supported by Chloe Sevigny who give a superbly understated performance as his wife who takes second place to the Zodiac killer.

Robert Downey Jr is occasionally funny but mostly irritatingly arrogant as the San Francisco Chronicle crime writer who sinks in to alcoholism. And Mark Ruffalo, while all good and hairy, is just a bit, well, meh.

David Fincher clearly directs his cast members well, but on the other hand there is very little of Fincher's stylistic direction that was present in Fight Club (1999), nor the grit, grime and edge of Se7en (1995) aside from the odd fanciful piece of camera work.

Perhaps that is it with Zodiac, there is no edge. The little tension that is built up at any one point is swiftly lost as we zoom years and years ahead to the next significant point in the investigation.

There is some attempt at tone; the film occasionally offers a dark and atmospheric look at San Francisco in the 60s and 70s. The opening sequence for example is chilling, with the emotionless execution set against the 4th of July celebrations. Much of the time however, the locations are nondescript. Location should be a character in itself in a narrative such as this, but here she is pushed into the figurative background.

There is a nicely played out underlying theme of addiction; the literal addiction of Paul Avery to alcohol and Graysmith's obsession with unmasking the Zodiac killer. The deterioration of both lives in different ways is contrasted nicely and effectively .

BOTTOM LINE: Not exactly killer, Zodiac is hard going at times. Worth slogging it out for Jake Gyllenhaal's brilliant performance as Robert Graysmith though.