Opening last June, the Off-Broadway hit The Countess has become the longest-running drama of the 1999-2000 season. Written by first-time playwright Gregory Murphy, the show unfurls the 19th-century love triangle between renowned art critic John Ruskin, his spirited wife Effie, and Pre-Raphelite painter John Everett Millias. The drama revolves around Ruskin's abhorrent behavior to his young wife and Ruskin's attempts to intervene. This searing exploration of obsession, cruelty and insanity has been the Off-Broadway rarity, a quality show that has been filling its seats. The production is playing at the Samuel Beckett Theatre, located at 410 West 42nd Street. Tickets can be purchased through Ticketmaster (212-307-4100) or online at www.ticketmaster.com