Two revolutionaries. Two juicy roles. Two brave actors.

Akeem Davis and Susan Riley Stevens will play Marcus Garvey and Emma Goldman in MARCUS/EMMA, a radical new play by Mary Tuomanen. Opening Wednesday at InterAct Theatre under Rebecca Wright's direction, it promises to provoke conversation at the least, arguments at the most, and raised eyebrows guaranteed.

First some background: Marcus Garvey (1887-1940) was a Black Nationalist, the founder of the Pan-African movement, and a proponent of what would become, in our time, Black Is Beautiful and Black Lives Matter. A self-educated, charismatic orator from Jamaica, he was hounded by the FBI and eventually imprisoned.

The FBI hounded and imprisoned Emma Goldman (1869-1940), too. An Eastern European Jewish anarchist, a proponent of free love and economic equality, "Red Emma" was a powerful orator, inciting crowds to protest.  Her legacy can be seen in the Women's Liberation Movement and the Occupy Movement. She founded the magazine Mother Earth. Best quote: "If I can't dance to it, it's not my revolution."

So, the question of MARCUS/EMMA is how can Garvey and Goldman dance together?

Their fierce and erotic onstage debate (the original title was Marcus Garvey and Emma Goldman Have Hot Hot Sex) is mostly invented by the playwright. Tuomanen is passionate about politics — her eyes suddenly fill with tears when she talks about social justice — and about what she sees as the country's desperate need for dialogue. And because she is also an actor and a director (wearing all three hats this month as she performs Hello! Sadness! and directs Walken), theater is her medium of choice, especially because it's a collaborative art. "If you don't want to be in a puppy pile," she says, "do something else."

A petite blonde whose delicate looks belie a mighty spirit, Tuomanen is dazzlingly articulate. Talking about writing MARCUS/EMMA, she told me, she had been reading their speeches and "thinking about Hegelian dialectic and thinking about sex, and thinking if these ideas could have sex with those ideas. ..." The result is a sexy play with a good deal of nudity. "It's about how the disparate elements of the political left can come together and create solidarity, and how sex can be liberated from property," she says. "There is no taking a break from revolution."

Playing a famous orator is one of the play's challenges. Garvey's style was "percussive, rapid-fire," while contemporary people are more used to Obama's measured rhetorical style. Davis is looking forward to the big speeches when both Marcus and Emma make appeals to the theater audience and have to "fire them up." His own oratory on the phone is impassioned as he defines Garvey as a hero: "He's one of my patron saints, and I walk with him daily."

Both roles require nudity. Davis reveals: "I was coming from the gym on my way to rehearsal and wondering, 'Do I look good naked?' I have issues with my body, as everybody does, but the play has been a beautiful challenge. Then I thought, 'The work I want to do is me, naked, sharing my self, my soul.' Nothing we do will be gratuitous. I'm excited about it."

Unlike Davis, Stevens has not had a history with her character. "I knew the name," she says. "I associated her with the word anarchy, and that was the beginning and end of my knowledge." She regrets not having paid more attention to history in school, but the topic "seemed to me dusty and foreign and, you know, not many women."

Nudity is surely a challenge as well for a woman "of a certain age." Stevens confesses that she hopes there won't be too much time spent standing around naked: "That sounds like a certain kind of hell. Much of the time, Emma is trying to get Marcus to have sex with her, and I have all kinds of feelings about this. When I first read the play, I thought, 'How awesome, how liberating.' But this is definitely outside of my comfort zone." When she explored why that might be, she wondered whether it was her personality, or whether it was that there were so few roles for women that demand that sort of unabashed sexuality.

Stevens believes that Goldman's sense of political power was tied to sexual power. Is the sex a metaphor for union? Sure, but it's also itself. "I know when I get to the point where I'm comfortable with the role," she says, "it will be so empowering!"

Empowerment: Exactly the point of both Garvey's and Goldman's political philosophies, and it's exactly the point of MARCUS/EMMA.

MARCUS/EMMA. Through Feb. 12 by InterAct Theatre Company. Proscenium Theatre at the Drake, 302 S. Hicks St. Tickets: $15-$38. Information: 215-568-8079, www.interacttheatre.org/.