There's shy, and then there's outright shrinking, hide-your-head-in-a-hole shy. David Morse, who plays hapless Dr. Jack Morrison on NBC's St. Elsewhere, has squeezed his 6'4" frame into the latter category. "He can be painfully nonverbal," says old friend Patricia Wettig, whose St. Elsewhere character, a divorcée of uncertain background, will marry Morrison on the show's premiere this week. "Anytime you're talking to him, you're not sure if he's with you or not."

Usually more like not. He sits in the dining room of his L.A. home flashing little-boy-lost looks at his visitor, making no attempt at chitchat, letting his wife, actress Susan Wheeler Duff, take care of social amenities. How would he describe himself? "Tall," he answers, laughing. Then he tries again: "As someone embarrassed to talk about himself, I guess."

In an industry that subsists on self-hype, such reticence scarcely promotes steady employment. In fact, Morse, 32, had to read for his part three times before being cast by St. Elsewhere's producers. "I think they were uneasy," he says. "My quality as a human being isn't always one that makes people feel comfortable."

Yet the producers not only hired him but fleshed out his role to reflect Morse's unique personality. Indeed, with his sensitive soul and craggy good looks, Morse has become something special—a thinking woman's upscale heartthrob. Vulnerable and offbeat, St. Elsewhere's perennial victim (his character has been widowed, beaten and raped) makes a peculiar sort of sex symbol. "Women don't want to see him with his clothes off," says St. Elsewhere co-producer Tom Fontana. "They want to mother him. Even his silences and stammers—you just feel like you want to take care of him."

Born in Beverly, Mass., Morse was raised with three younger sisters in nearby Hamilton. His father, Charles, is a retired sales manager for Sylvania; his mother, Gacquelin, is a teacher. Although he remains close to his parents, David says he found their marital problems painful when growing up. "I was young when they were going through their troubles, and they divorced when I was 18, so obviously home wasn't a pleasant place to live."

Auditioning for a play as a high school freshman, Morse found that acting was "an unexpected outlet for my behavior. My way of dealing with situations at the time was to try and become the center of attention so I didn't have to think about my life and insecurities." After graduating from high school in 1971, he joined the Boston Repertory Theater, then moved to New York in 1977 and became involved in the Circle Repertory Company. Between stage work and waiting tables, Morse made a film, 1980's Inside Moves, and several TV movies before getting the St. Elsewhere casting call.

In 1981 he met Philadelphia's Susan Wheeler Duff von Moschzisker (her real name, eventually shortened for professional purposes) while she was bartending in a New York restaurant. Typically, it took Morse a few days to work up his nerve to ask for a date, then another week to muster his courage to goon the date. Infinitely patient, Susan, 27, who's done episodic acting on TV, laughs as she remembers how their June 19, 1982 wedding came about. One night, after a year of steady dating, David asked, "Have you ever thought of getting married?" Recalls Susan, "I said, To whom?' I knew he was proposing but I had to let him take the initiative. Instead there was this long silence. Finally I said, 'Do you want to get married?' He said yes and that was it."

Now he has another wedding on his hands. Jack Morrison's marriage to the enigmatic divorcee—a new character—will be the centerpiece of St. Elsewhere's premiere and pivotal to the show's plot during the next few weeks. However that marriage turns out, it's got to be better than what he's been through so far. Since the hospital series debuted in October 1982, Morrison has seen his wife killed and young son kidnapped, been temporarily crippled, stripped of his diploma, dumped by his girlfriend and raped by inmates of a prison where he was performing community service. "It's definitely going to get better for Jack," promises co-producer John Masius, "but it isn't going to be Miracle on 34th Street." Morse remains skeptical. "I think they're having too much fun with Jack for things to get better," he says, smiling faintly, then retreating again into shy silence.