LOS ANGELES -- ROSE AND WALSH is mostly about a ghost--the ghost of Neil Simon.

The famed author of such rich, vital plays as Brighton Beach Memoirs, Biloxi Blues and Barefoot in the Park is but a memory, a phantom in his 30th play, ROSE AND WALSH, now in its world premiere run at the Geffen Playhouse.

Based vaguely on the relationship between Lillian Hellman and Dashiell Hammet, Simon has opted not to deal with them as they were--a complex, hard-drinking, gutsy, politically involved couple battling the world and their own demons. Instead, he gives us a near-blind, whining old shrew (Jane Alexander) whose husband (Len Cariou) has been dead for five years but still dominates her every waking moment. She not only conjures up his presence but talks to him out loud, appealing to him for help, inviting him into her bed, berating him for leaving her a widow. Only she can see and hear him, of course.

Such a plot contrivance has been the basis for many a movie and play, yet Simon dusts it off and tries to pass it off as fresh and original, without success. Never has a Simon play seemed so cliched, so phony and one-note. To be sure, there are a few funny lines sprinkled throughout, but they do not a comedy make. Even Simon seems to recognize that, leading him to eventually pour the sentimentality on like syrup on pancakes.

ROSE AND WALSH's story line goes like this: because Rose is so broken up over Walsh's death, she can't write any more. This puts her in a financial bind (despite living in a Bridgehampton beach house--elegantly designed by John Arnone--that must be worth a cool million). Walsh comes to the rescue, telling her about a manuscript that he hid away before his death. It's a masterpiece, of course, one that will surely find its way to the top of the best-seller list--if someone can only finish the last third.

Since Rose is too far gone mentally and physically to take on the task, she turns to her "caretaker" Arlene (Marin Hinkle) for help. A handsome young woman, Arlene just happens to have read a first novel by a talented young writer who did not achieve commercial success. And wouldn't you know it, the fellow lives just down the road from them, in a "poor" section of the Hamptons.

Clancy (David Aaron Baker) is a beer-swilling prole who takes the job on because he needs a paycheck. He also gets the hots for the cool, cultured Arlene, who has a surprise or two up her cashmere sleeve that is meant to stun the audience (most of whom have seen it coming from scene one).

The playwright (and director David Esbjornson) take an hour and fifty minutes to move Rose to the point where she is finally able to let go of her creepy, obsessive love for the wisecracking Walsh. An important issue between Rose and Marin is also resolved in the climactic moments of this spectral imitation of a Neil Simon play.

(At the Geffen Playhouse, 10996 Le Conte Ave., Westwood.
Call (310) 208-5454.)