There are lots of characters in the Off Broadway thriller “Harry Clarke.” But they’re all played by Billy Crudup — who gets lonely up there sometimes.

“It gets incredibly lonely,” admits Crudup (“Jackie,” “Spotlight,” “Almost Famous”) on the latest episode Stagecraft, Variety‘s theater podcast. A Tony winner for “The Coast of Utopia,” the actor holds the stage solo for the entirety of the 80-minute monologue, and he’s learned that you can’t get too in-your-head when you drop a line or two.

“As soon as you start doing that, you forget everything,” he laughs. “And then all of sudden, you’re in a tunnel, and it’s dark outside, and there’s nobody else onstage. That’s when you feel really lonely.” He’s always found his way back on track — but “during the interim, there’s a pretty intense chemical dump when you break into a flop sweat and you want to retire.”

On this episode of Stagecraft, Crudup discusses the challenges of playing an American pretending to be an Englishman, or several Englishmen, in the David Cale play, which recently began a commercial Off Broadway run (produced by Audible) following a hit run at the Vineyard Theatre. (An audio version of the play is already available on Audible, as part of the company’s move into theater content.)

The actor also reveals why he’s remained so committed to theater work even as he’s juggled screen projects. He talks up a few of those movie gigs, too — including his cameo in “Justice League” that led to a part in an upcoming DC Extended Universe film, “Flashpoint.”

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