Ethan Hawke

Ethan Hawke is nominated for an Academy Award for best adapted screenplay (with Julie Delpy and Richard Linklater) for "Before Midnight." (Kirk McKoy / Los Angeles Times)

The 10 films nominated for this year's Academy Awards for original screenplay and adapted screenplay tell diverse and distinctive stories: those of a couple squabbling on a Greek vacation, an Irish mother searching for the child she was forced to give up, a Texas electrician turned AIDS activist, and a con artist compelled to work with the FBI on a corruption sting, to name a few.

But a common thread emerged among many of the screenwriters in their reactions to the nominations, one stressing the primacy of fully fleshed characters.

In the category of adapted screenplay, Ethan Hawke is nominated with co-writers Julie Delpy and Richard Linklater for the relationship drama "Before Midnight." The film is the third in a series starring Hawke and Delpy and directed by Linklater, but Hawke said writing it wasn't any easier this time around, despite having an intimate familiarity with the characters Celine and Jesse.

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"It only gets harder, because as you get older, these characters become richer and more complicated," Hawke said on the phone during a layover in Houston shortly after the nominations were announced. "It becomes more difficult to create three-dimensional human beings, because older people are just more complex. Things happen to you and people respond in different ways."

Of the trio's writing process, Hawke said: "Usually what happens is about 90% of what we write gets thrown out. The audience is left with the best that we could come up with over nine years."

Also nominated for adapted screenplay are Steve Coogan and Jeff Pope for "Philomena," Billy Ray for "Captain Phillips," John Ridley for "12 Years a Slave" and Terence Winter for "The Wolf of Wall Street."

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Reached on the phone at a Los Angeles hotel, Pope talked about his approach to adapting Martin Sixsmith's nonfiction book "The Lost Child of Philomena Lee," about a retired Irish nurse trying to reunite with the son she was forced by the Catholic Church to give up for adoption decades earlier.

When making films based on true stories, Pope said, "There’s a tendency to take a step back and try to knock the rough edges off the story — to fictionalize it in order to conform to a classic structure. For me, I think it’s the opposite that’s the right way to dramatize a true story, which is to go deeper and deeper into the story, to really get into the DNA of it. Because in there, you’ll find things that you couldn’t possibly create."

For original screenplay, Craig Borten and Melisa Wallack were also nominated for a film based on a real person: "Dallas Buyers Club," about Ron Woodroof, a Texas man who contracts AIDS and begins smuggling unapproved drug treatments for himself and others to survive.

The film was two decades in the making, and Borten, speaking on the phone from his home in Santa Monica, said with a combination of relief and elation, "We pushed this thing up a hill for so long and felt like Sisyphus, and here we are today."

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The project began back in 1992, when Borten met and interviewed the real Woodroof just months before he died. Those tapes, and Woodroof himself, gave Borten and Wallack what they needed to see the film through.

"We just started with characters," Wallack said. "The characters are so amazing. Ron Woodroof is such an amazing person, so just have that gifted to you as a writer is so incredible."

Also nominated for original screenplay are Eric Warren Singer and David O. Russell for "American Hustle," Woody Allen for "Blue Jasmine," Spike Jonze for "Her" and Bob Nelson for "Nebraska."

Singer, whose script was inspired by the FBI's Abscam sting of the 1970s and '80s, said in a phone interview that there are two ways to approach fact-based stories: "You can either hold it to the truth and try to be as accurate as possible and have it be a docudrama," he said, "or you can just let go of it, let go of the truth, and speak to the truth of the characters, speak to the truth of the story that’s evolving," as "Hustle" ended up doing.

The 86th Academy Awards will be presented March 2 at the Dolby Theatre in Hollywood.

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Oscars 2014: Complete list of nominees