After taking a "Plunge" to open the season (Christopher Kyle's comedy/drama Plunge, to be exact), and then wallowing in "Mud" (Lynne Nottage's Mud, River, Stone), Playwrights Horizons understandably finds itself a bit "Gun-Shy."

That's the title of Richard Dresser's latest comedy, about a divorced couple whose separation proves as unsuccessful as their marriage. He's taken up with a young blonde woman on a no-food diet; she's dating a neurotic schlimazel with back trouble and a lingering rage against the ex- wife who cheated on him.

Gun-Shy began previews Jan. 13, opened to mixed reviews Feb. 1, and ends its scheduled run Feb. 22, after 23 previews and 25 regular performances.

Jeffrey DeMunn co-stars with Maryann Urbano, alongside Jessalyn Gilsig (Mere Mortals), Christopher Innvar and Lee Sellars. DeMunn's credits include Hedda Gabler (1994 at the Roundabout) and One Shoe Off (1993 at Off-Broadway's Second Stage Theatre).

Gloria Muzio, who staged Other People's Money, directs this comedy by the author of The Downside, Alone At The Beach and Bed And Breakfast. Dresser's Below The Belt starred Judd Hirsch Off-Bro d was produced by San Diego's Old Globe Theatre in May. Designing Gun-Shy are Allen Moyer (sets), Jess Goldstein (costumes) and Peter Kaczorowski (lighting).

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Also on tap for the Horizons season:
Tom Donaghy's From Above (April 17-May 24. Opens May 10).
Donaghy's Northeast Local played at Lincoln Center Theatre in late 1995; his Minutes From The Blue Route was a minor hit for the Atlantic Theatre Company last season. Other plays include Down The Shore and The Dadshuttle.

From Above has a "Martin Guerre"-style twist to it: a young widow is approached by an appealing stranger who claims to be her husband.

One surprising aspect of the 1997-98 Playwrights Horizons season is the absence of a musical, since recent years have brought viewers the award winning Violet, Floyd Collins and Jack's Holiday. Perhaps a musical will spring out of the "New Theatre Wing" series, held on the second floor Studio Theatre. Now in its 11th season, the Wing "provides playwrights, composers and lyricists the opportunity to develop their newest, and often boldest, work."

Tim Sanford serves as artistic director of the 26-year-old Playwrights Horizons, located at 416 West 42nd St. For more information about Playwrights Horizons' season call (212) 279-4200.

-- By David Lefkowitz