At La Cartoucherie, a former munitions factory on the outskirts of Paris and the home of Ariane Mnouchkine’s legendary avant-garde Théâtre du Soleil, the prolific American playwright Richard Nelson is holding a master class in naturalistic storytelling. His splendid Our Life in Art, which he also directs, is about the Moscow Art Theatre’s tour of America in 1923 and one hard day’s night with the ensemble around a kitchen table in a Chicago boardinghouse. The play’s title echoes Konstantin Stanislavsky’s celebrated autobiography, My Life in Art, and foreshadows the fine linguistic filigree to follow. The simple pronominal shift from “My” to “Our” telegraphs the play’s own distinctive point of view: this is a family portrait of the Russian troupe surviving in a foreign land, “a fictional account based on known facts,” according to Nelson. It is the best American play I’ve seen in many seasons. —John Lahr