ENTERTAINING : California Parties--Past and Future : When Hollywood Drinks : The Thin Man and James Bond agree: When it comes to a proper martini, it’s shake, never stir.

The secret of a Big League curve ball? It’s all in the wrist. But for a first-rate martini pitcher it’s all in the hips, if you believe William Powell, or rather his incarnation as Nick Charles, raffish sleuth of “The Thin Man” and the silver screen’s cocktail expert. Indeed, when movie audiences first meet Nick Charles, he’s holding court in a swanky gin mill. The camera pans the room of sophisticated revelers, and in the corner of the club, next to the bar, we notice a man gleefully dancing, not with a woman but with a cocktail shaker. He’s instructing the tuxedoed bartenders on the perfect martini beat.

“See, the important thing is the rhythm,” he says, never missing a step. “Now a Manhattan, you shake to fox-trot time. A Bronx, to two-step time. But a dry martini you always shake to waltz time.”

Then he pours the mixture into a waiting glass, olive ready, and with a flourish places the glass on a silver tray. It is immediately served back to him. He lifts the glass to his nose, savors the fumes and downs the thing. He’s his own best customer.

You aren’t likely to find such a character in today’s movies. It’d spoil the image of such modern heroes as John Rambo or Dirty Harry to be seen dancing with anything less lethal than a .44 magnum. But in the Golden Age of Hollywood, the only magnums shot were the kind that held Champagne. In celebrations, scenes of young love or tableaux of the haut monde , Champagne was a star. It was also a handy plot device.

In “Ninotchka,” Greta Garbo tastes the joys of capitalism with her first glass of the bubbly and is hooked. In “The Philadelphia Story,” several glasses of Champagne (or as Cary Grant’s character calls it, “the great leveler”) jostle Katharine Hepburn off her high horse just long enough to make her realize she’s about to marry the wrong man. Walt Disney’s Dumbo even discovers that he can fly under the influence of the fizzy stuff.

But as a dramatic prop, the cocktail is more versatile than Champagne: Sophistication, seediness or loneliness can all be determined by a character’s call at the bar. Cocktail parties were all the rage in the ‘30s and ‘40s (all that industrial-strength Prohibition hooch cried out for mixers, and the tradition stuck). The smartest couple on the screen always had a well-stocked bar, and the leading man’s better half was expected to be a sport and keep up with the boys--Myrna Loy as Nora Charles, finding hubby Nick sipping his sixth martini, promptly orders six for herself. “Line ‘em up,” she tells the waiter.

In “Casablanca,” Humphrey Bogart is the hero most remember, but Paul Henreid got the girl and the most interesting drinks. Bogey spends most of the film drowning his sorrows in bourbon, straight. But when the very together Henreid escorts Ingrid Bergman to Rick’s place, he orders Cointreau and, later in the evening, a Champagne cocktail (usually made with a dash of angostura bitters, sugar and a twist of lemon). The next night Henreid drinks cognac. It’s only when talking man-to-man with Bogey that he drinks whiskey.

A man of sophistication doesn’t simply drink well; he knows how to mix a drink, too. This invaluable talent rightfully impresses Carole Lombard’s well-to-do family in “My Man Godfrey.” William Powell (yes, again) as Godfrey charms the lady of the house with a concoction called a Bloody Angeli ca that manages to cure the hangover of the Angelica in question. Godfrey calls his drink “a focusing agent” and is elusive about its ingredients. However, we learn that it involves a pinch of mustard and, like a Bloody Mary, tomato juice. (Angelica tells Godfrey: “You can run amok on the vodka.”) Godfrey scores points with a European socialite (Eva Gabor) when he recalls her drink: French vermouth with a dash of cassis and a soda chaser.

As the ‘50s began, Hollywood’s love affair with cocktails was showing signs of strain. In “All About Eve,” Bette Davis’ character prefers her Scotch straight. At one point someone offers Davis’ Margo Channing a bottle of soda water to mix with her drink, only to be met by the steely gaze of those infamous Bette Davis eyes. As Joseph Mankiewicz, the film’s Oscar-winning director and screenwriter, put it in the script: “She looks at it (the soda bottle) and at him, as if it were a tarantula and he had gone mad.”

Later, Davis throws a big bash but serves her guests inferior liquor. When the bartender asks, “Does Miss Channing know she ordered domestic gin by mistake?” Davis retorts, “The only thing I ordered by mistake is the guests. They’re domestic, too, and they don’t care what they drink as long as it burns.”

Although “The Apartment,” made in 1960, shows the “martooni” (as one character calls it) still going strong enough, the film features libations that would have made Nick Charles reach for his gun: frozen daiquiris in a Chinese restaurant, the deservedly obscure rum collins, and a Tom and Jerry made with hot whiskey (or bourbon), eggs, sugar, Jamaican rum, cinnamon, cloves and hot milk. Ray Walston (pre-Martian) brings his own, arriving by cab to Jack Lemmon’s pad armed with his mistress and four long-stemmed glasses filled to the brim with the vile brandy and creme de menthe mixture known as a stinger.

Clearly the cocktail, while surviving, had lost its classic reserve. As the ‘60s progressed, the cocktail was mostly used as date aid for bachelors on the make. Meanwhile, Richard Burton and Elizabeth Taylor in “Who’s Afraid of Virginia Woolf?” didn’t really care what they drank as long as there was ice. By the time “A Clockwork Orange” was made--its futuristic Korova Milkbar, served not liquor, but drug-spiked milk--the cocktail was in big trouble. Fortunately a few good drinking men were still around--suave, sophisticated men who could hold their liquor with style: men like James Bond.

Thanks to his creator, Ian Fleming, 007 has perhaps the most detailed drinking preferences of all of Hollywood’s star characters. Not only should a James Bond dry martini be shaken (never stirred despite the fact that shaking will cause the ice to start melting), it should be served in a deep Champagne goblet. In “Casino Royale” Fleming gives the exact recipe for the perfect Bond martini: three measures of Gordon’s gin, one of vodka, and half a measure of Kina Lillet, shaken until ice-cold, and served topped with a large, thin slice of lemon peel. Unfortunately for easily disillusioned Bond fans, martini experts point out that Kina Lillet has quinine in it and would tend to make a martini bitter.

One of Bond’s favorite alternatives is bourbon on the rocks--Old Grand Dad, Walker’s Deluxe or I. W. Harper, please. He’s also partial to old fashioneds and Negronis (1/3 gin, 1/3 Campari and 1/3 red Cinzano). In outdoor cafes, say in Paris, Bond shuns vodka, whiskey and gin. Although Pernod is proper for such an occasion, legend has it that Bond won’t drink the stuff because the licorice taste reminds him of his childhood. Instead, he drinks Americanos (Campari, Cinzano, soda and a large slice of lemon peel) while dining alfresco.

Unfortunately, James Bond cannot single-handedly save the world for cocktail fans, and frankly, it’s much easier for bartender-less party hosts if their guests drink beer, wine, or the hard stuff straight or on the rocks. The obvious drift is toward the simpler drinks. Except for the occasional vamp, that’s what we’re seeing on the screen. But if you long for the concoctions of former days, we recommend Hollywood’s Musso and Frank. It’s benefits: a star-studded clientele (many from the good old days); movie-set decor ( real red-leather booths), and a bartender who never forgets a face. Here Hollywood’s Golden Age lives on--and the martini is still king.