With its dry, deadpan tone, “Living With Yourself” is a show that might not work half as well without Rudd’s inherent duality.

Of course he can handle the role of New Miles, the guy who seems always to have a spring in his step and a smile on his face. At an August breakfast in Manhattan’s West Village, Rudd was as charming as advertised. Clad inconspicuously in a baseball cap, T-shirt and shorts, still sporting his summer vacation beard, he was conscious of his celebrity without indulging in it, as when he spoke credibly about taking the subway like a civilian. (“If I talk to somebody, they’re like, ‘Why are you riding the subway?’ Because I need to get somewhere!”)

But “Living With Yourself” also allows Rudd to find the humor and the humanity in the old, original Miles: a man who was already struggling to fulfill his modest ambitions and must now contend with an unwanted doppelgänger, whose very existence creates standards he can’t live up to.

The truth is, there is a certain amount of the old Miles in Rudd, too : The actor knows how it feels to want the same seemingly fundamental things as everyone else — and to be misapprehended in those pursuits. He wants to feel that he is good at what he does and is expressing himself through it, but he also wants to hold on to a sense of commonality and privacy that he sometimes feels is slipping away.

When it comes to his work, Rudd said, “I don’t have any sort of grand statement to make, to anybody. I don’t want people to know that much about me, really. I don’t have much of an interest in being an open book.”