Classes in creative dramatics reveal more than talent for a group of relative strangers in Annie Baker's charming, but never completely satisfying, Circle Mirror Transformation, now at Playwrights Horizons' Peter Jay Sharp Theatre.

Led by Marty (the redoubtable Deirdre O'Connell channeling a warm Earth Mother persona), four students, including Marty's husband James (Peter Friedman in an understated but powerful turn), gather for six weeks in a mirrored rehearsal room at a community college in Vermont to immerse themselves in theater games. In the process, they share more of themselves than they might have expected, exposing vulnerabilities that they might have preferred to have kept hidden.[...]