Sometimes there's a joker or two ("Sicko," "Super Size Me") tucked into the documentary nominees.
Not this year.
All five contenders deal in a straightforwardmanner with serious, even dire, subjects. Meanwhile, foreign film contenders took subtle approaches in works with strong political subtexts.
Documentary subjects include the rapid degradation of the world's oceans and wildlife ("The Cove"), the way factory farming may be hazardous to your health ("Food, Inc."), and the clash between digital technology and old-style government repression ("Burma VJ: Reporting From a Closed Country").
Several films steer toward clear viewpoints. "I feel like we're not trying to make a movie, we're trying to start a movement," said "Cove" director Louie Psihoyos, a photographer and environmental activist.
Robert Kenner's "Food, Inc." evokes the muckraking advocacy journalism of Upton Sinclair's "The Jungle." That's because some of the problems with early 20th century food production haven't gone away, he said. "It's shocking to see how far backward we've gone" in policing what we put in our mouths, he said.
The other two nominees are "The Most Dangerous Man in America: Daniel Ellsberg and the Pentagon Papers," about the legendary Vietnam War whistle-blower, and Rebecca Cammisa's "Which Way Home," about railroad-car-hopping Latin American child migrants.
Whether a study of authoritarian cruelty in a provincial German village in 1913 ("The White Ribbon"), or a documentary-like exposé of Arab-Israeli conflict ("Ajami"), the foreign film nominees depict societies in radical, often violent, transition, grappling with uncertain futures while struggling to heal old wounds.
Not that they ignored character study or genre elements. Jacques Audiard's "Un Prophète" (A Prophet) is essentially a crime picture about a young, illiterate Arab man trying to survive a six-year sentence in a prison ruled by a Corsican Mafia gang.
The Argentine entry "El Secreto de Sus Ojos", which arcs from the '70s military junta era to 1999, is a dramatic thriller with a romantic subplot.
Like "Secreto," Michael Haneke's "The White Ribbon" -- which won the Palme d'Or at last May's Cannes festival and also earned a cinematography nomination for Christian Berger -- is structured as a flashback to a national trauma that may help unlock the present.
Peruvian director Claudia Llosa's testimonial, "The Milk of Sorrow," also skips backward in time -- to the 1980s and early '90s -- when her Andean homeland was riven by a brutal civil war between the government and the communist Shining Path movement. Inspired by a Harvard anthropologist's study, her movie posits that women raped by soldiers during the war have passed on their emotional scars through their breast milk, psychologically if not literally.
For Peruvians, Llosa said, the war is like a body that's still unburied. "So it's important and necessary to talk about it," she said.