The Harry Potter star is the sole cast member in Dickens' Women, which is currently touring the U.K., and she plays 23 of the author's characters during the show.
Margolyes is relishing the experience, but admits it's taking its toll on her as she yearns for company on stage.
Speaking on U.K. morning show BBC Breakfast, she says, "I'd much rather be in a play with other people, to be honest, because I love the interaction that we have onstage, fellow actors, but I'm very good at this. This is me at the height of my powers, I'll never be better, so I'm glad I'm doing it.
"If anybody wants to offer me another one-woman show, please don't. (It's) lonely, I'm someone who longs for talking to people like we're doing now and sharing ideas and confidences with other actors - stories, anecdotes. I love that."