FOR A MOVIE STAR, SHE DOESN’T ACT THE PART

Ally Sheedy’s favorite line in “Short Circuit,” where she plays a pet lover who befriends a runaway robot, comes when she first sees the oddball mechanical wonder invading her living room. Convinced that the robot is actually a visitor from outer space, she gleefully exclaims, “I knew it would be me!”

“You know, if I met a Martian--a real one--I’d probably say exactly the same thing,” Sheedy said, munching on an avocado-and-rice-cake sandwich at her favorite Malibu health-food eatery.

It’s easy to understand why Sheedy was so at home with her spunky character in “Short Circuit.” The young actress displays such a beguiling sense of innocence that it hardly seems surprising that her favorite memory of a visit to Scotland is of a trip across moonswept fields where she was convinced “there was a leprechaun around every corner.”

Seeing Sheedy at a local playground, watching tots play on the swings, you almost get the feeling that she could spring right out of a movie by Bill Forsyth, the Scottish director whose films are populated with elfin spirits and magical occurrences.

An avid reader, she said she’s happiest keeping diaries and notebooks filled with stories, poems and character sketches. In turn, she sees film making as an extension of imagination. “Splash,” the story of a mermaid come to life, is one of her favorite movies.

“The playfulness of film is the most important part of the process,” she explained. “You can’t take it so seriously that you start worrying about whether this character is going to make or break you. You lose all the joy that way.

“I really blossom when I’m making a movie. I love figuring out what my character should look like, what should she wear, what does she like to eat. It’s like being in a warm, wonderful cocoon. When I’m between shots on the set, I feel as if I’m in suspended animation.”

Hearing her childlike fascination with film making, it’s easy to forget that at 23, Sheedy’s already a show-business veteran. She danced with the American Ballet Theatre at age 6, wrote a best-selling children’s book at 12 and has appeared in eight films, including “The Breakfast Club,” “Twice in a Lifetime” and the two current releases, “Blue City” and “Short Circuit.”

Her enthusiasm has made Sheedy a favorite with her directors. “This is one of the most un-actressy women I’ve ever worked with,” said John Badham, who directed Sheedy in both “Short Circuit” and “WarGames.”

“It’s hard to believe Ally grew up in New York City--you’d think she’d be more sophisticated and worldly-wise. All too many actresses are given to airs and pretensions--you can hear the wind whistling through their ears. But Ally is so sensitive and sweet, with such a native intelligence, that you’d swear she was the hairdresser on the set, not the star of the picture.”

Sheedy is friendly with several card-carrying Brat Packers (a label she finds “condescending”). But she avoids the trappings of stardom, arriving for her interview without a trace of makeup and driving an aging Jeep with a bumper sticker that reads “Visualize World Peace.” (Sheedy has several favorite causes, which include a new hospital at Marineland for ailing sea life and fund-raising activities for Sen. Alan Cranston.)

She said she prefers staying at home with her boyfriend, musician Steve Ross, reading a good book--she counts her current favorites as Milan Kundera and J. D. Salinger. She’s already begun writing one novel, but said she’s put it away “till I grow up more and have more experiences” to bring to it.

“It’s really important to me that I don’t get any preferential treatment. When I do write something, I’ll do it under another name, maybe my sister’s, ‘cause she’d probably like that,” she said with a sly grin. “I just don’t want people to hate the book because it’s by an actress, and if people do like it, I want it to be because they liked the book, not me.”

If Sheedy seems less spoiled and self-indulgent than many of today’s young actors, it’s perhaps due to the strong influence of her parents. Her father is a New York advertising executive and her mother, Charlotte Sheedy, is a literary agent and was an early feminist organizer.

“Both my parents were tremendous achievers, but I think my mom was more of a role model,” she said. “When I was young, she left my father and went back to school. I remember when I was 8, I answered the phone and she was calling me from jail--she’d been at an anti-war demonstration--and instead of stopping the war, they arrested her.”

However, her mother was unimpressed by her daughter’s early acting efforts. “She was very strict and her first reaction to my doing commercials was that if my values changed in any way, I’d have to stop. She told me that if she caught me standing in front of a mirror, she’d never let me act again.”

Sheedy laughed. “In fact, she wouldn’t even let me wear a bra for a long time.”

When her mother was at Columbia University, Sheedy would tag along, wandering around campus on her own, imagining herself playing different parts. “I’d walk around, pretending I was Elizabeth I and my sister had been captured by outlaws and . . . well, it was much more fun than watching TV.”

Sheedy stared at a wildflower garden nearby. “You know, when I was little, I thought these little fairies and elves slept in the flowers and if you got up early enough, you could see them getting back into the blossoms. That was just me. I was always making up dreamy stories in my head--you know, about mermaids and leprechauns--and I’d act out all the parts myself.”

Of course, most young actresses in Hollywood don’t get such enchanted roles. In Sheedy’s first film, “Bad Boys,” her character was raped, while in “The Breakfast Club” she played a disturbed high-schooler. In “Blue City” she teamed up with Judd Nelson (a frequent co-star) in a murder mystery where the pair try to solve his father’s death.

The film bombed with the critics and taught Sheedy--who candidly admitted she didn’t “particularly like” the film--a valuable lesson. “Michelle Manning and I had been close friends,” she said. “And she was so excited about the chance to direct that my feeling was that it would be great to work with someone I really liked and help contribute to their first big project.

“I was very naive, I guess, because I kept hoping it would turn out OK, that somehow all the stuff that was missing would miraculously appear when they edited it all together. I guess that’s not the way it works, so I was disappointed.”

Still, Sheedy doesn’t shy away from challenges, especially when it comes to auditioning for new roles. “Listen, I miss out on parts all the time,” she said. “It can be heartbreaking. You get very disappointed. Sometimes, I’ll just go home and cry and cry.

“But the great thing about auditions is that you can surprise yourself. Even if I don’t get the part, I’ll be astounded by how much I pushed myself and the peaks that I reached in my performance. If I feel as if I challenged myself and impressed the people who didn’t think I was right for the part, I’ll be high on that for weeks, even if I didn’t get the part.

“I just really believe that if things are meant to be, then they’ll happen.”