When actor Michael Willis, playing the homophobic porno-producer Mr. Astro in Woolly Mammoth's current production of "Half Off," is shamed into literally kissing the behinds of the other characters onstage, you just can't help but pity the guy. Sure, he's a prejudiced scumball, but Willis's pathetic, doughy puss, his smirky delivery, the way he lowers his hulking frame to the floor -- all create a likability factor that isn't present in playwright Harry Kondoleon's script. A baby-faced Michelin Man in a sand-colored suit, Willis makes us laugh -- and feel -- in spite of ourselves.

Those who frequent this city's smaller, more adventurous theatrical venues -- Woolly Mammoth and Round House in particular -- know that Willis has become something of a master at conjuring up both mirth and menace. The 44-year-old actor won a Helen Hayes Award for his heart-wrenching performance as a retarded man working hard to make a life for himself in Round House's 1989 production of "The Boys Next Door." And as a veteran Woolly member, he's spent the past seven years playing a succession of over-the-top types in way-out productions -- but has stamped each with his reality-based, feet-on-the-ground approach to acting.

"Mike's so tangible, so there," says Woolly Artistic Director Howard Shalwitz, referring both to Willis's round, rather imposing form and his technical aesthetic. "He's not comfortable doing caricature. He's always trying to find something grounded, something real that he can connect with. No matter how far out on the edge I push him in terms of craziness, he'll hold down the center."

And find the soul in even the most contemptible character. Willis can play a nut case nurse obsessed with aliens and UFOs ("Tales of the Lost Formicans"), but also get at the loneliness and longing at the root of this loony behavior. Or find the dignity in an utter dope like "Mud People's" Buzzy. New York Times critic David Richards said it best when he described the actor's vibrantly sleazy portrayal of Otis De Marko, the LaLaLand producer of last season's Woolly production of "Strindberg in Hollywood": "He's the inveterate back-clapper, the consummate negotiator and the great white whale, rolled into one. ... On the surface, he's accommodation itself, but underneath, where the ulcers grow, he's at odds with everyone and everything."

"The thing that always impresses me about Mike is how he just commits from the get-go," says fellow Woolly company member Jennifer Mendenhall. "When you sit down for that first read-through, most people will be searching and unsure. But Mike just kind of opens his mouth and it's there -- whole."

Jerry Whiddon, actor and artistic director of the Round House, says: "I find it refreshing to be with him, because I tend to be Mr. Angst."

"I can't create this ethereal character unless there's some basis in reality," Willis explains. "I don't care how crazy the play is -- you have to create the characters out of whole cloth and, hopefully, make them believable for your audience. The worst thing that can happen after a play is over is for a guy to turn to his wife and go: 'Pizza?' I want them to have some sort of catharsis, to walk out saying, 'I didn't know what it was about, but Jesus, I'm thinking about it!' "

Grounded, the perfect word to describe Willis's approach to his craft, pretty much sums up his personal life as well. No bohemian, unstructured, rent-due type of existence for this fellow. Spend a couple of hours at his comfy Silver Spring home and you're gazing at a Portrait of the Artist as a Suburban Family Man. His daughters, ages 2 and 4, greet you at the door (their 7-year-old brother is at school). A black Labrador hangs out in the corner. Downstairs, Willis's wife, Lori, taps away at her computer; she's doing her part for Trice Talent Services, the payroll company for union performers and their employers that the couple runs. The business, she affably explains, "is the mortgage payment."

Hunkered down in a big leather lounge chair in his office at home, Willis is set to schmooze. "I'm one of two right-wing actors in the whole world, I think," he says. His wonderfully rumbly, ready laugh follows. "Traditionally theater has been sort of a ..." He lets out a cascading Twilight Zoney whistle and sends his finger spiraling to suggest the ozone layer. "In the old days, you never associated with actors because all they would do was run around and have sex and talk funny. But my values -- going to Vietnam, believing what I was doing was right for my country -- have always been different."

Willis's father was in the service, which meant the family moved around a lot. After flunking out of North Carolina's Methodist College he enlisted in the Air Force. Upon his discharge in 1975, Willis joined his family in Washington and went to work as a computer specialist for the United Mine Workers.

His profession "didn't make for much of a social life," so when somebody suggested that he get involved in community theater, he took up the challenge. The annual Hexagon revue in Georgetown proved his salvation. He made friends, and the director saw a lot of potential in the fledgling actor. Willis began auditioning for small roles, then meatier ones, and cracked the dinner theater circuit playing "second banana" parts like Nicely-Nicely in "Guys and Dolls." Eventually he made the big move to downtown venues -- first New Playwrights' Theatre during its early '80s heyday, then Woolly, which he now regards as his artistic home.

He also quit his full-time job, opting instead for a freelance existence writing corporate newsletters and churning out articles for real estate pullouts in the Gaithersburg Gazette.

"They'd send me out to these new developments and I'd just walk through and then go home and write things like, "Among the other amenities are a Jacuzzi where you can have sex with your wife with the water spraying all over the room." The laugh explodes. "And I also wrote theater reviews -- but I changed my name for those." (He's now a regular contributor to the trade publication Backstage, but he uses his real name.)

In his eminently practical, meat-and-potatoes style, Willis also plunged into the world of commercials and industrial films. (He's also gotten occasional opportunities in "classy" films such as "Tin Men" and "Hairspray.") Unlike many of his colleagues, he revels in the instant education these one-day gigs offer. "I think they're wonderful," he says of the more than 300 industrials he's done for MCI, IBM, the IRS and other organizations. "You get so comfy with the camera. And being a character actor works to my advantage."

There's another, darker side to Willis's utter groundedness: the literal, weight-related one.

"The worst review I ever got was one in which David Richards said he couldn't envision me being the recipient of romantic attention," says the actor, who has always been, shall we say, ample. "I mean, my wife loves me! It's hard when you don't look like everybody on that show with the Zip code in the title -- your self-image says, 'I can't play a love scene because I don't look like them.'

"I remember one time I was feeling really good, walking to my car. I had just done a performance, and I'd also been on a diet for four or five months and was at the point where I would salivate at the mention of food. A car of toughs went by, and one yelled, 'Hey, ya fat {expletive}!' Just because I was walking along the street. And here I was starving to death in this body."

Woolly Mammoth's Shalwitz says the two qualities he most admires in Willis's acting -- "a very intense kind of rage that comes from this sense of being persecuted, and this incredible sort of need, this desire to belong" -- may very well stem from what Willis has experienced as an overweight person. Because Shalwitz himself has never been interested in what he calls "the casting of pretty people," he has provided Willis with a series of challenging roles, for which the actor is grateful.

"Woolly has freed me up," Willis explains. "When I come out there and people are throwing themselves at me, we're talking nontraditional casting. I am it!"

The weight problem is not only a professional consideration. Ten years ago, at the age of 34, Willis -- who was also a heavy smoker at the time -- had a heart attack.

"It was just a real sobering wake-up call at the beginning of our relationship," Lori Willis says. "Not many people have the privilege of spending their six-month anniversary in the primary care unit of a hospital."

Never the nagger, Lori waited for Michael to take control of his eating. A couple of years ago, he gave up red meat. Since February he's been off dairy. The pounds are gradually dropping off, his cholesterol has dropped, and he admits to feeling a whole lot better. But the food fantasies haven't ceased.

"I would like nothing more than a pile of greasy pork barbecue and a side of fries slathered in ketchup," he says with a sigh. "But those days are gone, man."

Greasy barbecue aside, Willis is, all in all, a fairly contented guy. In a town filled with frenzied workaholics and frustrated artists, he's fashioned a career and a life that's comfortable and child-friendly.

"There are a lot of things that are important, but not many that are serious -- like Vietnam and heart attacks," he muses. "I'm, as they say, keeping my options open. But I have no desire to leave Washington.

"I'm not going to get out of the way if the train hits me," says Willis, referring to the outside chance that some casting director in New York or Hollywood will fall in love with his work. "But if I can be this dilettante who sits in Washington and says, 'Yeah, send me out on that job,' that's fine with me."