Why would Hugh Grant, the dashing young Englishman who has charmed Hollywood and women everywhere with his bashful grin, pay for sex?

The question had Hollywood atwitter after Grant's arrest early Tuesday as he allegedly indulged in a sex act with a Sunset Boulevard prostitute in his white BMW.

''What's he doing out there picking up his thrills on the street? He could have sat at the Four Seasons bar and had action in three minutes,'' said Maryanne Norbum, West Coast bureau chief for the Globe, the supermarket tabloid.

It would appear that the suave, 34-year-old Grant could have anything he desires: He's got stardom, wealth, good looks and a loyal following after movies that include ''Four Weddings and a Funeral,'' ''The Englishman Who Went Up a Hill But Came Down a Mountain'' and the upcoming ''Nine Months.''

His live-in girlfriend is Estee Lauder's new shapely model Elizabeth Hurley, who showed up at this year's Cannes Film Festival in a jaw-droppingly revealing dress. They've been together about eight years.

Grant was in Los Angeles to promote ''Nine Months,'' about a guy (Grant) who finds out he's going to be a father. Shortly before 1:30 a.m., vice officers allegedly saw Divine Brown, 23, walk up to Grant's car and get in.

''They were later observed to be engaged in an act of lewd conduct,'' Officer Lori Taylor said.

Both Grant and Brown were booked for investigation of misdemeanor lewd conduct in a public place and released without bail for arraignment July 18. They could get up to six months in jail.

Lewd conduct covers such offenses as fondling, oral sex and intercourse. Taylor refused to identify the sex act.

Grant's publicist, Sandy Rice, didn't return repeated telephone calls.

Entertainment industry observer Art Murphy doesn't think Grant's career will be damaged.

''Nowadays I think people might just raise their eyebrows at the indiscretion of it all,'' said Murphy, who analyzes box office performance for the Hollywood Reporter. ''It depends on the public's perception of the performer. It would probably be commercially disastrous if he were playing a missionary priest opening Friday.''

Grant played such a character in ''Sirens.''