Kevin Kilner is leaving the original cast of Donald Margulies' marital themed Dinner With Friends, at the Variety Arts, March 19, further breaking up the old gang that helped make the show an Off-Broadway smash.

Kilner was to have left one week earlier, on March 12, but extended his stay for a week. Jonathan Walker will step into Kilner's role March 21.

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Dinner With Friends, opened Off-Broadway Nov. 4, 1999, with Matthew Arkin, Lisa Emery, Kilner and Julie White. White left the show after a few months and was replaced by Carolyn McCormick. Arkin and Emery remain with the show.

Margulies, the author of Collected Stories, cooked up a serious comedy drama about a dissolving marriage and the disillusioned friends left behind. Daniel Sullivan (The Heidi Chronicles, I'm Not Rappaport) directs. The rueful comedy about divorce and unsure friendships, was previously seen at Actors Theatre of Louisville and (in a revised form) South Coast Repertory Theatre. In New York, the play has been embraced as intelligent, dry and grown-up.

The world premiere of the four-character, two-couple Dinner With Friends (about a pair of successful food writers, and an artist and a lawyer) was part of the 1998 Humana Festival of New American Plays at Actors Theatre in Kentucky. The revised version was staged by Sullivan at South Coast Rep in Costa Mesa, CA, in October 1998.

Designers in New York are Neil Patel (set), Jess Goldstein (costumes), Rui Rita (lighting).

Actor Arkin appeared on Broadway in Laughter on the 23rd Floor and in Off-Broadway's You Should Be So Lucky. Emery has appeared in New York in Far East, Burn This, Curtains and Marvin's Room. Kilner starred in The Glass Menagerie opposite Julie Harris in New York.

Dinner With Friends is produced by Mitchell Maxwell, Mark Balsam, Ted Tulchin, Victoria Maxwell, Mari Nakachi and Steven Tulchin.

The Variety Arts Theatre is at 110 Third Ave. at 13th Street. Call (212) 239-6200 for ticket information.

-- By Kenneth Jones