The most appealing aspect of "Charlie Chan and the Curse of the Dragon Queen" -- a ragged but diverting parody of the venerable detective series -- is the romantic comedy teamwork of Richard Hatch and Michelle Pfeiffer.

A delightfully ingenuous couple, they portray Lee Chan Jr., the over-eager, blumbling, half-Jewish "number-one grandson" of the great detective, and his equally wide-eyed, clumsy fiancee, a society girl named Cordelia Farrington III.

Peter Ustinov, no doubt a mandarin at heart but never particularly inspired when doing ethnic Chinese shtick, is cast as Chan -- previously inpersonated by eight other film actors without intentional displays of facetiousness, although the role had certainly settled into camp cliche by the time Sidney Toler was through with it at Monogram in the late '40s.

In the latest version, now at area theaters, the distinguished sleuth is lured out of retirement in Hawaii to investigate a serious of murders in San Francisco. A distinctively ghastly M.O. suggests that this crime wave is the work of the notorious Dragon Queen (Angie Dickinson, a decorative rather than playful choice for a slinky femme fatale ), recently sprung from the pen.

Thirty years earlier Chan had sent her up for the too-perfect murder of pineapple baron Barney Lupowitz. One of the consequences of this case was the marriage of Chan's son Lee to the Lupowitz heiress Brenda -- the union that produced Lee Jr., who resides at the San Francisco mansion of his melancholy, overprotective maternal grandmother (Lee Grant), still devoted to the memory of poor adulterous Barney. A hero-worshipping chip off the old block, Lee Jr. has been haplessly pursuing a career as a private eye in Chinatown. His only client to date is a Girl Scout seeking her lost cat, and he owes her for cookies.

The humorous company is filled out by retainers and minions of the law. The late Rachel Roberts, Roddy McDowall and Johnny Sekka are in fine form as mournful Mrs. Lupowitz's servants -- a jumpy cook, an insolent butler and an elegant chauffeur, respectively.Brian Keith, getting a rare opportunity at farce, is also excellent as a seething policeman, frustrated by the ongoing murder wave ("Not another Bizarre Killing!" he moans. "Don't killers use guns anymore?") and irket at his solicitous young partner, Paul Ryan.

The script by Stan Burns and David Axelrod is consistently knowing and funny, but Clive Donner's direction seems hectic and uncoordinated at several points, particularly when elaborate sight gags are in order. Both the framing and editing are askew, and the comic timing suffers. For example, when Lee Jr. unwittingly leaves chaos behind him on the streets of Chinatown or a slapstick chase sequence with carriages and police cars is staged in Golden Gate Park, the results seem funnier as ideas than as finished sequences. If there's a character in the story whose behavior personifies Donner's problems, it's the skittish maid played by Roberts, whose dropped platters have their cinematic equivalent in his fumble-fingered montage.

The mutual ardor and solicitude of Lee and Cordelia are often expressed in slapstick klutziness. When first seen together, they rush to embrace and end up rolling down a hillside. They get all tangled up holding hands or trying to help each other up a ladder. Hatch and Pfeiffer -- both veterans of various TV series -- give the characters deftly coordinated movements and reactions to enhance their temperamental affinity as naive sweethearts. In the most winning episode, their dumbness becomes a miraculous life-saver. Trussed up and confronted by a vicious guard dog, they hit upon a method of disarming the beast that is at once ridiculous and wittily effective, provoking justifiable cheers and applause from the audience.

As Chan, Ustinov's principal mannerisms are narrowed eyes and a perculiar droning sound, which may indicate thought or sheer annoyance. He's adroit with the proverbial chestnuts, spoken in Austere Pidgin, like "Absence of suspicion often note presence of danger." There's a good moment when he discovers his grandson in a Charlie-Chan disguise and tries to explain things as gently as possible: "Detective disguises you need to disguise self, not to disguise self as other detective." One of the best gags in the show plays with the same idea. While walking through the Tenderloin, Charlie is noticed by a pimp who takes an immediate liking to his suit: "Hey, white-on-white, that's all right!" The next day every pimp on the block is dressed like Charlie Chan.

While in production, the film inspired protests from some Chinese-American groups in San Francisco. Their efforts may be responsible for the abundance of Chinese-American bit players and extras in the movie, but it would be difficult to promote a boycott on the basis of such a cheerful, harmless, inconsequential movie. The idea of Charlie Chan as a figure of symbolic ethnic significance seems rather quaint at this stage of the character's evolution, which has pretty much petrified into affectionate comic senility. Ustinov's canny and dignified Chan is neither triumph nor affront, and it would seem prudent to let well enough alone.