For actors there’s often an epiphany, a realization that suddenly makes every element of a performance fall into place.Sometimes it’s instant. Sometimes it happens over a long period of time. And sometimes it doesn’t happen at all. “The first night with an audience is when it happened for me,” says Sean Hayes, nommed for his toplining perf in tuner revival “Promises, Promises.” “The one character we didn’t have yet was the audience, because I speak to the audience a lot in the show. So once I had that last piece of the puzzle, that’s when it started to pop for me,” he adds. It happened early in the preview process for Hayes, but it came late for Jude Law, tapped by the Tonys for his Hamlet. “I didn’t have an epiphany moment until about a month from the end,” he says. “We had done nearly five months of performances and there was just a sense, in the last month, of absolute cohesion. I thought that the last month was going to be the most exhausting physically, but I felt the most confident.” It also got him wondering what it would be like to play the part a different way in the future: “I had done it 200 times by the time we finished, but looking back on it, I’m thinking, Maybe there’s another way of doing this.” While Law tackled the best-known role in the Shakespeare canon, Sherie Rene Scott, nominated for the autobiographical musical “Everyday Rapture,” was faced with the challenge of playing herself. “The epiphany came when I was clear enough to say that I could play a character named Sherie Rene Scott, who has similar dilemmas as myself and some similar personality traits but who wasn’t me, so I would feel safe performing it,” she says. What’s the stage-Sherie like? “She’s a bit of an asshole,” Scott admits. “But in a different way than I am.” Douglas Hodge did some real-life research to play a transvestite in “La Cage aux Folles.” “I went to a drag club in Birmingham,” he reveals. The contrast between the fierce onstage quipping and the fairly squalid backstage area got to him: “I realized the people I know who had the thickest armor were the most vulnerable. Once I had that, I really had a way into the character.” Katie Finneran figured out how to play her scene-stealing supporting role in “Promises, Promises” as soon as she knew who was cast as the female lead. “I knew for sure when Kristin Chenoweth was cast I wanted to be the antithesis of her,” Finneran says. “High heels, dark clothes. For the voice, Sally Kellerman comes into play.” David Alan Grier has had plenty of defining moments in creating his lawyer character in “Race.” “I’ve had several, and I’ve been wrong,” he says. “You think you have it and you revel in that, and then you kind of lose it and you go, What happened? Then you find your way back to it. It’s an ongoing process.” For Stephen McKinley Henderson, nommed for his role in “Fences,” the know-how to play his part — one he’d portrayed in another production more than 15 years ago — came over time. The first time around, he hadn’t yet met August Wilson, and the scribe’s cycle of 10 plays wasn’t yet completed. Plus, he notes, he’s now older and can bring more life experience to the part. “If there was an epiphany, it happened over a long period of time,” he says. Sometimes epiphanies don’t happen at all. And occasionally, an actor, like Chad Kimball of “Memphis,” doesn’t feel he needs one. “There are roles that just make sense to you right off the bat, and this one kind of spilled out almost immediately, vocally, physically,” he says. Denzel Washington demurs when asked if he’d had an epiphany in playing his lead role in “Fences.” “No. It’s time to quit then,” he says. “That’s what’s great about live theater. You can feel one night like you nailed it and get a lukewarm response. You can feel like you were just off another night and get a tremendous response.” And then, of course, some actors don’t believe in epiphany moments at all — like Christopher Walken. “It doesn’t really work that way,” says the star of “A Behanding in Spokane.” Addie Morfoot contributed to this report.