Off-Broadway's longest running straight play of the 1999-2000 season, The Countess will mark its 600th performance on Dec. 1 at the Lambs Theatre.

The Countess traces the true-life love triangle and sensational Victorian scandal that ensued some 146 years ago when London society learned that England's art critic and trend setter, John Ruskin, was being sued for divorce by his charming and popular wife, Effie, on the grounds that their union had never been consummated. Ruskin's wife was instantly vilified, and it was later revealed that there was another man, John Everett Millais, a founder of the Pre-Raphaelite movement.

As reported earlier, first-time playwright Gregory Murphy's play is on a slow but steady course to become one of the longest-running non-musicals in Off-Broadway history The Countess ran 352 performances at the Samuel Beckett before an eviction forced the play to re-open at the Lambs Theatre on May 11, where it is still running. The Lambs transfer was the second for the show, which premiered at the Greenwich Street Theatre in March 1999.

There is one recent cast change to report: On Nov. 20, Janet Zarish (Minetta Lane’s Other People’s Money and TV’s “One Life to Live”) replaced Kristin Griffith (who is coincidentally married to Peter Maloney) as Lady Elizabeth Eastlake (Effie Ruskin’s confidante) in Countess. At the time of the transfer to the Lambs, there were two cast changes; Richard Seff replaced Fredrick Noonan and Anita Keal replaced Honora Ferguson. Other than that, producer/director Ludovica Villar-Hauser reported that the show has shown a certain stability. The Countess features most of the original players including leads Jennifer Woodward (Effie Ruskin) and James Riordan (John Ruskin), as well as Jy Murphy (John Everett Millais), John Quilty, Keal and Seff.

The production team for the show includes set designer Mark Symczak, costume designer Christopher Lione, lighting director Doug Filomena and original music by Dewey Dellay. Production manager is Andrew John Tucker. By comparison, Off-Broadway's top non-musical record holders include Tony 'n' Tina's Wedding (4,000 performances and counting), Vampire Lesbians of Sodom (1,840), Vanities (1,785), Driving Miss Daisy (1,195) and The Boys in the Band (1,002).

Tickets for The Countess run $55. The Lambs Theatre is located at 130 W. 44 St. For tickets and information call Telecharge at (212) 239 6200 or the theatre's box office at (212) 997-1780.

—By Murdoch McBride