This year entries for the Oscars Best Documentary category range from the heartwarming to the intimate, as well as tackling dark and violent subject matter.

Japanese artists Noriko and Ushio Shinohara are the subjects of "Cutie and the Boxer," directed by Zachary Heinzerling, but the film is focused less on the art they make than on their relationship. In the past 40 drama-filled years, wife Noriko yearns to break out of her role as an assistant to her husband, and to be an artist in her own right. The film won the Best Director award at the 2013 Sundance Film Festival.

"The Act of Killing," made by Texan-born director Joshua Oppenheimer, depicts the brutality of the anti-Communist government in Indonesia during the 1960s. Estimates put as many as one million people dead in a wave of violence after an aborted coup. The film has already won the 2014 BAFTA award for best documentary.

In "Dirty Wars," reporters Richard Rowley and Jeremy Scahill document the growing covert warfare-drone strikes and off-the-books military operations that have dominated the war on terror. Directed by Rowley, the film features Scahill as the face of the investigation into a troubling style of warfare. The film won the cinematography award at the 2013 Sundance Film Festival.

"The Square" is a street-level chronicle of the grassroots Egyptian revolution that toppled both Hosni Mubarak, and the military rule that replaced his government. The film fetched the audience award at the 2013 Sundance Film Festival. Director Jehane Noujaim and producer Karim Amer also went back to Tahrir Square after Sundance, to film the protests that pushed Mohamed Morsi out of office.

Rounding out the category is the biggest commercial success "20 Feet From Stardom", with global earnings at 5.2 million U.S. Dollars. Directed by Morgan Neville, the film chronicles a group of background singers, and follows their stories through pop music history.