Nine years ago Marilyn Hassett's rising career seemingly ended in a grotesque mishap while filming a hokey Opel TV commercial. She was stepped on by a frightened elephant, fracturing her pelvis and both legs. Crippled, she spent an anguishing year in beds and wheelchairs. "Doctors told me I would never walk again."

The rest of the script owes less to Hollywood than to O. Henry. Hassett has become a self-described "walking miracle" and, at 29, an increasingly important actress who next week begins the movie adaptation of Sylvia Plath's disturbing autobiographical novel, The Bell Jar. Ironically, the role that built her reputation—the true story of paralyzed ex-skier Jill Kinmont in The Other Side of the Mountain and this year's follow-up Part II—required her to draw on her own harrowing experience in the wheelchair.

Though the surprisingly successful Part I grossed $18.5 million since its 1975 release, Hassett resisted the sequel. The tear-wrenching script, she felt, "was an insult to the woman. I nearly threw up when I read the first draft." During the original Marilyn had met the real Jill and was "intimidated by her incredible strength. It was terrifying to have this presence roll onto the set every day while you're filming her life."

While Part II chronicles Kinmont's marriage to trucker John Boothe, Hassett simultaneously found love in her own life. Director Larry Peerce had picked her over 700 auditioners to star in Part I, even though her only previous credit was a brief dance-on in They Shoot Horses, Don't They? Peerce next gave her a bit in his Two Minute Warning, and the accident-prone Marilyn snapped an ankle in the football stadium mob scene. Finally, during the Mountain sequel, their "strictly platonic thing" turned into what Hassett calls "the most fulfilling relationship I've ever had."

Her own L.A. parents were divorced when she was 11, and Hassett recalls that "growing up was hard." She was cruelly teased by her Catholic schoolmates as "swivel hips" because of curvature of the spine. Other children taunted her with her car-dealer father's slogan "Hassett has it." At 15 she cut classes to model for swimsuit ads, "much to the dismay of the nuns." At college at Cal State's Fullerton campus, the painfully shy Hassett took drama "so I'd be able to look people in the eye without blushing." She hoped to join the Peace Corps but wound up driving a taxi in Beverly Hills, working in a bank and photographing record album covers. Success came with 39 TV commercials for clients like Pepsodent, Ivory Snow and Honda—before the elephant incident.

Hassett and Peerce, a divorcé, now live together, which is a first for her. In preparation for Bell Jar (which Peerce is directing), Marilyn read 15 books on Plath and learned to type. She also keeps a daily journal of her dreams and thoughts so "I can always look back and see where I was emotionally." Where she is right now is "terrified" of marriage but otherwise together, she reports. She works regularly with deaf and disturbed children, and finds acting brings similar rewards. "After Mountain One," Hassett remembers, "Jill called and said, 'Marilyn, I don't feel so bad. I realize now I don't look grotesque.' That," says Hassett, "pleased me more than anything else."