"When Bill Murray says, 'I love you,' he's in character, sincerely saying 'I love you,'" says a theater director I know. "But he's also acknowledging the audience, and his character, and the absurdity of both."

Murray's province, of course, is comedy. He is arguably the funniest comedian to have passed through the cast of "Saturday Night Live," and his droll delivery -- part smarm, part Novocain -- has been aped by a thousand lesser comics since. He starred in the highest-grossing comedy of all time (1984's "Ghostbusters," $239 million) and has brought the irreverent, improv style of Chicago's Second City and "SNL" to a wider audience than any of his contemporaries have. But his recent departures from comedy into ... well, not necessarily straight dramatic fare but certainly less comic roles (the school benefactor having a midlife crisis in "Rushmore," the alcoholic ventriloquist in "Cradle Will Rock," an unctuous Polonius in "Hamlet") put him in a whole new ballgame. He may never get that Oscar nod Jim Carrey seems to have his heart set on, but Murray probably wouldn't want to go to the Academy Awards anyway. Might interfere with his golf.

Murray grew up in a large Irish Catholic family (eight brothers and one sister) in the Chicago suburb of Wilmette, Ill. The chaos of his family life was mirrored in the opening scenes of "Caddyshack," the 1980 golf comedy written by his brother Brian Doyle-Murray. "Our house was a wreck," Murray recalled, "a constant claustrophobic mess."

As in many large families, Mom and Dad were the cause of much mirth, as both audience and inspiration. "My father was a very difficult laugh," Murray recalled in "Cinderella Story: My Life in Golf" (written with George Peper). "Adults found him very funny. But his children had a tough time cracking him up. One of my strongest childhood impressions is falling off my dinner table while doing a Jimmy Cagney impression. I hit my head very hard on the metal foot of the table leg, and it hurt terribly. But when I saw my father laughing, I laughed while crying at the same time. I guess that was some kind of beginning."

If Dad prepared the kids for tough crowds to come, it was Mom who offered some shtick they could steal. "All of us kids ended up 'doing Mom,'" Murray writes. "There are four of us who've tried show business. Five if you insist on counting my sister the nun, who does liturgical dance."

When they weren't trying to make their parents laugh, Bill and his brothers followed the Cubs, played a lot of baseball and caddied at the local course. Like his brothers Ed and Brian before him (he was first known around the course as "the new Murray"), Bill used the money he made to pay his tuition at Loyola Academy, a Jesuit high school. He attempted premed only to be thrown out of college when he was busted for possession of marijuana. Suddenly comedy didn't look so bad. By the end of the '60s, Chicago's Second City was one of the country's best-known improv groups. (The San Francisco group the Committee, co-founded by Second City alum and Murray mentor Del Close, was another.) In a recent history of the troupe, "The Second City: Backstage at the World's Greatest Comedy Theater," founding director Sheldon Patinkin described the improvisational games that became a staple of Second City's nightly revue: "The improvisational games aren't games in the sense of winning and losing, and they aren't about being funny. They're about being in the moment; they're about being totally present to each other onstage -- being 'in play.'"

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