"Bernie" won't be raking in the box-office dollars of writer-director Richard Linklater's and star Jack Black's last collaboration, 2003's crowd-pleasing "The School of Rock," nor was it ever likely intended to. An off-beat dark comedy with an assured indie spirit, the film is played largely for giggles despite a violent true-crime premise based on a Texas Monthly article by Skip Hollandsworth. This is where the picture runs into trouble, the tone remaining so frothy even in the face of a grisly murder that it's hard to take what happens seriously or to become emotionally involved in the goings-on. It doesn't help that the title character is kept at arm's length from the viewer, Linklater backing off from the natural instinct of creating a character study in lieu of a partial faux-documentary where conventional scenes are interspersed with the frequently acerbic talking-head comments of townspeople discussing their personal experiences with friendly mortician Bernie Tiede (Jack Black) and the widow he allegedly befriended and killed, Marjorie Nugent (Shirley MacLaine).

In the East Texas town of Carthage, Bernie is something of a hero, a good-boy-done-right with a steadfast Evangelical faith and a purity of heart that has made him the best assistant funeral director around. When Mrs. Marjorie Nugent's husband passes away, Bernie shows her a selfless caring that she's never known before. Despite being a nasty witch of a woman whose "nose was so high she'd drown in a rainstorm," as one resident colorfully puts it, Marjorie takes Bernie under her wing and makes him her right-hand man. Pretty soon they're going off on vacations together and Marjorie is signing over her will to him. And then, in a moment of frustration, Bernie shoots her four times in the back. No one seems to miss her as he carries on the charade that she's still around, but when suspicions grow and the body is found in the garage freezer, Bernie is indicted by District Attorney Danny Buck Davidson (Matthew McConaughey) on first-degree murder charges.

In "Bernie," the ripe mix of authenticity and satire seen in its documentary-style interviews are hugely entertaining, reminding of material straight out of a Christopher Guest movie. For his part, Jack Black (2010's "Gulliver's Travels") has rarely been better, goofily endearing yet suitable restrained. It would probably count as career-best work, in fact, were it not for writer-director Richard Linklater's undernourished and unfocused screenplay. The audience only really gets to see Bernie through the points-of-view of others, stripping him of the layers that make up his legitimate true self. What makes him truly tick? What are his intentions when he kills Marjorie at the 50-minute mark? Did he simply snap from her mistreatment of him, or was there an ulterior motive? Anyone searching for insight into this case won't find it here, the film never taking responsibility for the gravity of the subject matter. As is, Shirley MacLaine (2010's "Valentine's Day") plays Marjorie as lonely and a bit selfish, but not nearly the shrew necessary to believe it when Bernie reaches his boiling point and snaps. And then there's Matthew McConaughey (2011's "The Lincoln Lawyer"), pushed to the sidelines as D.A. Danny Buck Davidson. It's a spindly supporting part unworthy of the actor, and he clearly only took it due to his devotion to Linklater (the filmmaker gave him one of his first jobs in 1993's "Dazed and Confused").

Exaggerated or not, the flamboyant Deep South milieu of Carthage, TX, and Jack Black's always watchable performance come close to overshadowing the otherwise glaring pitfalls of "Bernie." The early scenes displaying Bernie's sterling work ethic at the funeral home are fascinating, as is his initial run-ins with Marjorie. From there, it is as if the story stops adequately developing, going through a robotic sea of plot turns without giving depth or empathy to anyone on screen. It reportedly took Linklater close to ten years to get this project off the ground, but what he's made is less inspired by "Fargo" than an apparent sitcom. For a motion picture about one person losing her life and another losing his freedom, "Bernie" doesn't deserve to be as flippant as it ultimately is.