Till death do us part, and after

And you thought Oscar and Felix were an odd couple. The characters at the center of Neil Simon’s new play, “Rose and Walsh,” making its world premiere at Westwood’s Geffen Playhouse, are an even odder couple: One is living, the other is dead.

It seems fair to reveal this little plot twist since the playwright does the same within the first few minutes of this quirky love story -- and it’s only one of many more twists to come in an erratic effort that, despite a few bright moments, plot-twists slowly in the wind.

According to the oft-quoted deathbed line from English actor/manager Sir Donald Wolfit: “Dying is easy, comedy is hard.” If “Rose and Walsh” is any indication, comedy about dying is really, really hard.

The play just doesn’t feel finished yet; opening night still felt like a preview, if not a dress rehearsal. In a recent Times interview, the stars of the play, Jane Alexander and Len Cariou, both observed that Simon was still handing the actors new pages at the 11th hour, and it shows.

In most cases, the scenes beg to be trimmed more than rewritten -- most jokes play out a couple of beats too long. In this production, directed by David Esbjornson, they’re zingers with no zing, rendered even less zingy by slow pacing; they should go by so fast that they’re gone before we realize they’re not very funny. And characters remain surprised by the plot twists for a page or two longer than anyone in the audience ever could be.

When the play was originally announced by the Geffen, it was described as “inspired by the relationship between writers Lillian Hellman and Dashiell Hammett. That comparison got thrown out along the way as Simon continued to change and rewrite. Doesn’t matter; just another indication that this one came down to the wire.

But if you’re interested in being present while one of the country’s most successful and prolific playwrights works out the kinks on a new comedy -- not something that happens every day in Los Angeles -- then the Geffen is the place to be.

Alexander plays Rose, a tough-talking, Pulitzer prize-winning writer now in her mid-60s and facing the decline of her career and her eyesight, as well as the loneliness of having lost her soul mate, Walsh (Cariou), another legendary writer whose “rhythms even Mozart would envy,” some five years ago.

At her summer beach house in East Hampton, N.Y. -- whose woodsy coziness is well-realized in John Arnone’s rustic set -- Rose is now struggling to come to terms with the fact that she is in the midst of a passionate, if conflicted, love affair with a dapper, wisecracking ghost. Cariou is indeed dapper in the role, but one too many wisecracks gets in the way of his charm.

Rose’s only flesh-and-blood companion is the moody Arlene (Marin Hinkle, who spent three seasons on ABC’s “Once and Again” ), variously described as her friend and her assistant, who is spending the summer at Rose’s home. The younger woman, also an aspiring writer, becomes an unwitting -- and unwilling -- witness to Rose’s bizarre relationship with her deceased lover.

Also part of this bizarre mix is David Aaron Baker as Clancy, a young but already washed-up hack who receives an intriguing invitation from Rose to become her partner in a mysterious new writing project. This development leads to some shtick about a “ghost writer,” and if you didn’t see that one coming and think it’s hilariously funny, you’ll probably enjoy much of the humor in “Rose and Walsh.” It also helps if you can conceive of the afterlife as much like taking the tunnel from New York to New Jersey.

Baker, suitably confused and disheveled as the beer-drinking Clancy, becomes the butt of the humor, such as it is, that comes of Rose speaking to a ghost only she can see and hear. This works -- once. Hinkle’s effectively cautious, reserved Arlene also gets caught in this tired cross-fire.

Surprisingly, this play is most effective, and most refreshing, when Simon drops the death jokes and the one-sided conversation gags and just writes it straight. There’s something potentially very touching and rich about the relationships between these characters and a love beyond the grave, and once in a while, Simon has the good sense to let them talk to each other.

Taking full advantage of those moments is Alexander’s Rose, whose eventual transformation from hard-edged anger to abject vulnerability is lovely and heartbreaking to watch. We don’t need another character to observe something along the lines of “if this were a war, she’d be the tank” to know there’s an armor here that needs to be broken through. In this elegantly nuanced performance, Alexander dares to bare her soul, even while “Rose and Walsh” is speeding through the tunnel to Jersey.

*

‘Rose and Walsh’

Where: Geffen Playhouse, 10866 Le Conte Ave., Westwood.

When: Tuesdays-Thursdays, 7:30 p.m.; Fridays, 8 p.m.; Saturdays, 4 and 8:30 p.m.; Sundays, 2 and 7 p.m. Added matinee Feb. 19, 2 p.m. No evening performance Feb. 23.

Ends: March 9.

Price: $28 to $46.

Contact: (310) 208-5454.

Running Time: 2 hours, 5 minutes.

Jane Alexander...Rose

Len Cariou...Walsh

Marin Hinkle...Arlene

David Aaron Baker...Clancy

Written by Neil Simon. Directed by David Esbjornson. Set design by John Arnone. Costumes by Elizabeth Hope Clancy. Lighting design by Stephen Strawbridge. Sound design by Jon Gottlieb. Production stage manager Elsbeth M. Collins.