Hey, Diane Lane and Donald Sutherland can only do so much

Eccentric families are dependable laugh-generators on film, especially if they're filthy rich, addicted to ridiculous social rituals and find themselves blessed with enough leisure time to land in trouble.

They also need to generate a lot of charm if they're going to sustain interest for a feature-length film. There must be a seductive method to their madness. "Fierce People" strikes out on that score before its adenoidal narrator, Finn (played by Anton Yelchin), finishes whining through his first lines. Rarely has self-pity become so monotonous so quickly.

It does help that Diane Lane brings a playful spirit to the role of Finn's blithely hedonistic mother, Liz. Donald Sutherland lifts each of his scenes as Ogden C. Osborne, the mysteriously benign billionaire who has all but adopted them. He's especially delightful performing an impromptu version of "A Pretty Girl Is Like a Melody."

Also lending some animation to the picture are Chris Evans as Osborne's lively and articulate grandson, Bryce, and Elizabeth Perkins as Osborne's sarcastic daughter, Mrs. Langley, whose chief role is to observe the nuts on the loose at the Osbornes' New Jersey mansion.

But it's impossible to ignore the fact that Finn is the center of the story — or that Yelchin fails to convince as a teenager who's appealing enough to bed Osborne's maid as well as his sensitive granddaughter, Maya (Kristen Stewart).

Director Griffin Dunne ("Addicted to Love") relies repeatedly (and unpersuasively) on establishing connections between the extended Osborne family and a South American tribe of "fierce people," the Ishkanani. They're seen in grainy 16mm footage provided by Finn's anthropologist father (the story is set in 1980, so he doesn't use video equipment).

The script by Dirk Wittenborn, who also wrote the novel that preceded the film, has trouble shifting gears when the narrative turns into a whodunit shocker. Like "Running with Scissors" and other recent dysfunctional-family comedies, "Fierce People" is too pleased with its own showy taboo-breaking.

John Hartl: johnhartl@yahoo.com