Helen Hunt fully invests in ‘The Sessions’

Helen Hunt says courage can take many forms. “Sometimes brave is saving someone from drowning,” the actress says. “This is a different kind of brave.”

Hunt’s version of fearlessness is her emotionally and physically naked performance as the sex surrogate Cheryl Cohen Greene in “The Sessions.” The movie, inspired by a true story, focuses on Mark O’Brien (John Hawkes), a Berkeley author who chiefly lives in an iron lung due to childhood polio. Approaching age 40, O’Brien, who can’t move any of his limbs but is not impotent, decides he wants to lose his virginity. He enlists Greene for the mission.

As written and directed by Ben Lewin, himself a polio survivor, “The Sessions” follows O’Brien’s panic over the conjugal visits and Greene’s struggles with his disability and her attachment to him. The movie, which won two awards at January’s Sundance Film Festival, is refreshingly, and often comically, candid about sexuality, “exquisitely and excruciatingly intimate,” in Hunt’s words.

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That frankness required a bold commitment from Hunt, the 49-year-old Oscar-winning veteran of “As Good as It Gets.” Greene talks about penises and vaginas the way a car mechanic discusses carburetors and oil filters. But sex therapy isn’t just about language; a surrogate’s job in most cases is to actually have sex with the client, so Hunt in “The Sessions” bares a lot more than her soul.

For Hunt, like any of her actor peers, it was an awkward offer: Here’s a great role in a unique tale, but your entire wardrobe will pretty much fit in this sandwich bag. “I was very predisposed to do it because there are so few good scripts — it just never happens,” says Hunt. “But anything less than the amount of nudity in the movie would be antithetical to the spirit of the movie.”

Lewin initially suggested that they figure out how to shoot the sex scenes on location, but Hunt insisted they carefully rehearse how the R-rated sequences would be staged, inviting Lewin and cinematographer Geoffrey Simpson to her guest house to choreograph body and camera moves. “You don’t just get there and work it out,” Hunt says.

The director said an equal challenge was Hunt’s balancing her character’s clinical detachment with emotional vulnerability, all while paying homage to but not mimicking the real person. “I think it’s a more complex character than Mark,” the writer-director says. “She’s so paradoxical: a middle-class soccer mom who has sex with strangers.”

For Hunt, who recently finished writing a movie about a mother and her son that she hopes to star in and direct, “The Sessions,” which opens Oct. 26, was impossible to pass over. “I’m not dying to walk into a sound stage and get naked in front of a bunch of people,” Hunt says. “I think what this proves is that I’m a whore for a good story.”

john.horn@latimes.com