US actress Meryl Streep, nominated for her 18th Oscar for "August: Osage County", on Friday said she was "very grateful" to be in the running despite having won three times.
Streep stars in the black comedy drama along with Julia Roberts as the "toxic" and strong-willed Violet Weston who gathers her family together after the death of her husband.
The film is based on the award-winning Broadway stage play by Tracy Letts who also wrote the screenplay.
"I saw the play seven years ago. I remember it hit all of us like a freight train ... I was entranced, it made me laugh and it shocked me," the actress told reporters in Paris where the film had its French premiere on Thursday.
Streep said actors were supposed to relish playing difficult characters but that the "reality is that where it begins, where it emanates from is a very unpleasant place."
"She has cancer in her mouth. She chooses to smoke constantly in the face of that, she has chemotherapy ... she's a drug addict ... it's all a toxic mix, a nasty place to live."
But she added that it was also liberating "to play a person who says exactly what she thinks, never with a cover, never, never being nice, no thought of diplomacy. So that's a wonderful free feeling".
Streep said she was thrilled at the Oscar nomination and that people were "still willing to look at my work and to look at it fresh".
"That is the most unbelievable thing, that they are not tired of me yet or of my work so I'm very happy about that. Very gratified," she said.
Roberts plays one of Streep's daughters in the film and has also been nominated for a best supporting actress for her role.
Other nominees in this year's best actress category are Amy Adams for "American Hustle", Cate Blanchett for "Blue Jasmine", Sandra Bullock for "Gravity" and Judi Dench for "Philomena".
Streep won best actress Oscars for "Sophie's Choice" (1982) and The Iron Lady (2011); she was named best supporting actress for "Kramer vs. Kramer" (1979).
The Academy Awards take place in Los Angeles on March 2.