In Dublin, an All-Male Lonely Hearts Club

The three men — one young, one middle-aged, one old — waiting in the antiseptic bus terminal barely acknowledge each other's existence. Yet each man's story evocatively echoes the others' in "Port Authority," the slender but affecting play by Conor McPherson that closes the Atlantic Theater Company's season. Written in 2001, a few years before Mr. McPherson's "Shining City" and "The Seafarer" (both recently produced on Broadway), "Port Authority" is steeped in loneliness. Even the format is...