“Zodiac” is director David Fincher’s latest return to his old stomping grounds- the crime movie.

It tells the story of the Zodiac killer who haunted the Bay Area in the late ’60s. Dead bodies begin to turn up, seemingly at random, and strange, cryptic notes about the murders get sent to the newspapers of San Francisco.

“Zodiac” follows two plotlines. The first one is about journalists Paul Avery (Robert Downey Jr.) and Robert Graysmith (Jake Gyllenhaal) getting the mysterious letters sent to them and how they get involved with the killings.

The second, more interesting plotline is about the investigators trying to solve the case.

That part of the movie pans out more like a straight crime-solving movie, but the twist is that it focuses on the tedium and frustrations of policework.

The red tape and the late night calls, miscommunication and lack of cooperation between the police districts; all the things that aren’t usually shown in police movies.

“Zodiac” is a movie about dark rings under your eyes, the frustration of following false leads and grasping at shadows.

Fincher uses the trivial in something as suspenseful as a serial-killer movie, and makes it intriguing. “Zodiac” almost plays out like a documentary in its sheer terseness.

The actual murders themselves are lacking in tension and are eerily banal in their execution. It works to great effect, and that the murders seem so normal is much more frightening than any given gore fest or slasher movie.

Fincher takes more of a backseat driver’s role in “Zodiac,” unlike his more visually and sensational movies, such as “Seven” and “Fight Club,” for good and for worse.

He lets the scenes speak for themselves, and gives the responsibility to the cast to drive the action.

Mark Ruffalo gives his best performance in years as lead detective David Toschi. He redeems himself from the horrible comedies he has put out in the last years, like “13 Going on 30” and “Rumor Has It.”

This is exactly the type of movie Ruffalo should be in, where his talent is put to use for something more substantial than cheap laughs.

The deterioration of the people who have to deal with the murders is the best part about the movie, and no one in the movie falls apart like Downey’s Paul Avery.

Avery goes from a successful crime reporter to an alcoholic, and despite his cynical attitude, Downey manages to deliver a haunting and wounded humanity. He is very much the moral compass of “Zodiac,” a compass that has lost its way completely.

Gyllenhaal does what is expected of him- he plays the good-looking weirdo that we have known since “Donnie Darko.” Nothing spectacular, but solid none the less.

His role as Graysmith is used as a narrative device to give the moviegoer a point of view in the sprawling, decade-long investigation, and for the first half of the movie it works.

It is in the last 45 minutes or so of “Zodiac” where the movie attempts to wrap everything up in a more traditional manner that it gets difficult.

The strength of the movie is its unusual approach to a usual type of movie, and trying to shoehorn a resolute ending to a case that basically never got a conclusion undermines that effort.

“Zodiac” is a long movie, clocking in at 160 minutes. It is the type of movie that needs to be long though. It does carry its time throughout, but despite that it does feel long.

It is nice to see a movie set in the ’60s and ’70s that doesn’t ramp up the funk-dials and kitsch. Yes, there is old school music in “Zodiac” and yes, they wear cleaner cuts of clothing. “Zodiac” however, doesn’t take it too far or make it too loud.

The look of the movie is somber and sparse. Don’t expect the grit and dirt and water damaged apartments that Fincher otherwise uses so commonly.

Despite the weak ending, “Zodiac” is a good crime flick and well worth seeing.