If you didn't know you'd signed on for a Sam Shepard play, you might spend the first minute of Ages of the Moon, now at the Atlantic Theater, wondering whether you'd accidentally happened upon one of those pithy character studies about a couple of codgers in their twilight years, matching each other shot for shot as they contemplate the imminence of death. Well, you have. But it is a Shepard play, so you can expect some freaky detours and the occasional depth charge. Also, sly humor -- lots and lots of it.

Ames (Stephen Rea) and Byron (Seán McGinley) are old pals of several decades' standing. They may have met working around horses (racetrack allusions are dropped), or perhaps just [...]