For the first time, Jennifer Connelly is having nightmares about her job. But the 36-year-old Oscar winner has played a cracked-out junkie (Requiem for a Dream), a haunted tenant (Dark Water), and a suicidal depressive (House of Sand and Fog), so it was only a matter of time. The role in question: a mother whose 10-year-old son is killed by a car in Reservation Road. "It's truly horrific, putting my head in that place," she says, phoning late at night after a long day on set. Her husband, Paul Bettany, is filming in Italy, and the thought of her alone, tucking in her own two young sons in their big, dark Brooklyn townhouse stirs damsel-in-distress instincts. Not that she's using a bedroom voice: "I can be really loud and raucous, and they sleep through it."

Raucous? More like courtly. Connelly speaks with an accent so proper that you feel the need to watch your mouth, and so determinedly crisp that—bad dreams or not—you get the sense she's going to be just fine, thank you very much. Besides, she dealt with worse while filming the action-thriller-with-a-moral Blood Diamond. Riding in an SUV with co-star Djimon Hounsou, Connelly suffered a concussion and a herniated disc, waylaying her in a South African hospital. "It was freaky," she recalls. "I had to wear a neck brace for a while, which was really sexy." She laughs. "It was good for getting good seating in restaurants and cutting to the front of lines. I kept it—just in case." To play a scribe who flirts with Leonardo DiCaprio, Connelly—a notoriously canny interviewee—turned the tables on real-life war correspondents, soliciting their elusive backstories. "They were indulgent and politely answered all sorts of invasive questions, from 'What do you pack?' to 'Who do you have sex with?' "

She is equally frank about her own motivations, especially her need to exercise, which the injury briefly curbed. A cross-country star at Stanford—for the record, she "fantasizes" about going back to school to finish her diploma—Connelly logs as many as six miles daily. There's also yoga, biking in Prospect Park, "extreme snowshoeing" (she clarifies that it's anything but), mountain climbing, tennis (she took lessons to help Paul perfect his strokes in Wimbledon), and skiing (the family retreats annually to Stowe). Now she's branching into music, with guitar and piano lessons. "The family band needs a pianist, I really feel it," she says. "Otherwise I'll just be consigned to backup vocals."

Connelly may be pushing for a Laurie Partridge gig, but she'll likely steal the show. As a jilted wife in Little Children—which leaves readers of Tom Perrotta's novel wanting more of her—she ionizes every scene with her tense, expectant air. Was it hard to display more affection for her son than her husband (Patrick Wilson)? "The thing about her is that's just what you get to see," she says, bristling. "They don't do her justice. She loves her husband, and does right by him, but he's the grown-up, and he knows how much she loves him." Wilson pinpoints Connelly's appeal on her emerald irises. "Even in the briefest of scenes or moments, she is able to command a vulnerability with her eyes," he says. "Which is probably why she's a big ol' movie star."

As an actress who growth-spurted under the klieg lights, Connelly copes by a) not watching her movies after they come out, and b) having a sense of humor about her turkeys—which are all the more accessible in the Netflix/YouTube era. "There are a couple real doozies out there," she confesses. "I did an Italian horror movie where I communicate with insects—it's a horrendous performance." Now that she's patented the role of the despairing wife/girlfriend/mother, Connelly is looking for a comedy and might break the taboo of working with one's spouse. "When we find the right thing, we hope to be able to do it together," she says. It might draw scrutiny to their low-pro Park Slope routine, but Connelly will coyly beat it back. Asked what her friends tease her about, she volleys with the skill of an accomplished tease: "What do your friends tease you about?"

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