Zodiac (15)

The running time is too long although, in Fincher's favour, the movie maintains a brisk pace throughout the search for Zodiac, the serial killer who terrified the San Francisco Bay area from the 1960s to this day.

He's never been caught despite a massive police investigation and exhaustive research by newspaper cartoonist-turnednovelist Robert Graysmith. He's one of several men whose obsession with the case has an impact on both their professional and personal lives.

Graysmith, who likes doing puzzles, is first intrigued by the coded messages sent to San Francisco newspapers by the killer bragging about his murders.

Gradually the whole case, which has incidents spread over four police areas, over a number of decades, leads him to quit work and neglect his family, when not employing his children to help sift through the mountains of paperwork evidence.

Ruffalo is the homicide inspector David Toschi who, with partner William Armstrong (Edwards), follows the trail of clues left by Zodiac but keeps coming up against a brick wall.

Downey Jr is the San Francisco Chronicle's crime reporter whose life takes a downward spiral as he becomes too close to the case and begins to fear for his own life.

Fincher stages several creepy set pieces as Graysmith and the authorities come tantalisingly close to uncovering the identity of the killer - a mother with a baby who accepts a lift from a stranger, some of the murders themselves, and Graysmith's panic as it dawns on him that he might be talking to Zodiac in person.

It's a long haul to the inconclusive ending, but the combination of a whodunit and the way the investigation takes over the lives of those pursuing it make Zodiac worth the nearly three-hour endurance test.

Stars: Jake Gyllenhaal, Mark Ruffalo, Robert Downey Jr, Anthony Edwards, Brian Cox, Chloe Sevigny, John Carroll Lynch
Running time: 157 mins
Rating: Four stars