Ask director Robert O’Hara about casting for his latest project, the new musical Gun & Powder, and he’ll tell you that his leading ladies came as a package deal. Emmy Raver-Lampman, one half of that deal alongside Solea Pfeiffer, recalls him telling the cast, “It was very clear from day one that Emmy and Solea weren’t going to do this without the other one.” And while neither Raver-Lampman nor Pfeiffer ever articulated it that way, they knew it was true.

“This is my older sister,” Pfeiffer tells Playbill of her affection for her co-star. The two aren’t blood-related, but you would never know it. Plus, they’ve spent more of their time together as sisters than not—first as Angelica and Eliza Schuyler on the first national tour of Hamilton, and now as twins Martha and Mary Clarke in Virginia’s Signature Theatre production of Gun & Powder.

The Hamilton tour bonded these women in an intangible way. Especially on the road, they depended on each other and built shared memories, laughing and venting, while also sharing a mutual admiration. “I’m inspired by her as an artist,” says Pfeiffer of Raver-Lampman. “It’s rare, having that combination of artistry and friendship and fun.”

Which is why it seems a no-brainer the two reunite for this new musical, inspired by real-life sisters. Written by librettist Angelica Chéri and composer Ross Baum, Gun & Powder puts pen to paper on Chéri’s own family lore. “Many times we’d open the family photo album, turn to the faces of Mary and Martha, and immediately ask, ‘Who are these White women?’” Chéri notes in an interview in the show’s program, but “they were in fact Black women and in fact our distant aunts.” With a Black mother and White father, Chéri says, “They just passed for White.” The musical takes place in the 1890s, post-slavery, when Mary and Martha’s mother lands short on cash to pay the rent. The two decide to pass to earn better money, but a train ride gone wrong leads them down a path of lawlessness—and love.

Through Mary and Martha, Pfeiffer and Raver-Lampman find a new kind of sisterhood. “There is no other preconceived versions about who they are supposed to be,” says Pfeiffer, as was the case when other actors had originated Angelica and Eliza. This time, “we are the standard. We get to have complete ownership over them.” Raver-Lampman adds, “Having the opportunity to create a sister bond of our own, that hasn’t already been established by other women before, and to set that tone for the show and have it be believable that we really are sisters, is important.”

The two work as much as they can to take the same stances, hold the same type of energy to them, and communicate through glances onstage to illustrate their sisterhood. “I think about some of the basic acting exercises you do, like mirroring, and maintaining hyper-awareness of the person who you’re onstage with,” says Pfeiffer.

“Even in the moment, I’ll see Solea doing something on the other side of the stage, and I’m like, ‘Oh, I like that, and this is an OK moment for me to imitate that,’ and so I’ll try to incorporate it on the spot,” Raver-Lampman interjects. “These girls are twins,” Pfeiffer says, “and when you have lived your whole life with somebody, you are going to be aware of everything they do without even thinking. And I think that was a thing for us.”

Though Raver-Lampman and Pfeiffer appear physically different at first glance, this conscious work and their emotional connection render their sisterhood a palpable reality.

That and the fact that they relate on another significant level. “We have had very similar experiences being biracial women,” says Raver-Lampman. “There is a kindship in that.

“On our first read-through, I was so choked up unexpectedly when I said to the writers, ‘I have never played myself before ever in my life,’” she continues. As mixed race actors, the two share the feeling that “we can fit anywhere but nowhere.”

“Mixed race people, or ethnically ambiguous people, have found themselves in this weird spot where you’re wondering what you are allowed to claim and what you are allowed to even audition for, and it really falls on the actors to hope that they’re not making a wrong decision. Because it’s a weird thing when visually you are one thing, but by blood you are another.” says Pfeiffer. “You see a lot of breakdowns lately for ‘this character is mixed race,’ and that always irks me because that shows to me that [the creators] are trying to check a box. Mixed race could mean a million things.”

With Gun & Powder, these women feel empowered that they are not, as Pfeiffer puts it, part of “a diversity quota for this project.” Instead, “we are the project.”

But even as the two lead the musical side by side, the heart of the story arises in the polarization of their experiences. And both work to highlight the contrast. “The more alike we are at the top of the show, the more heartbreaking it is to see them lose each other,” says Pfeiffer.

“Martha is the gun,” says Raver-Lampman of her character. “Mary is the powder; she is the softer, lighter, fluffier side of the twins. Martha’s this harder, cold, steel-ish one.”

The story unveils two manifestations of the biracial experience, and not just that of the 1890s. “Even now you see there is a pressure to assimilate and to change yourself to fit a mold to feel more safe, or to feel like you will earn more money, or to feel like you will have a more comfortable life,” Pfeiffer says. “So there’s a lot of things that happen in this story that are totally mirrored in 2020 and the reality of colorism in America.”

As these women continue the world premiere engagement of the Broadway-aimed production, both relish the opportunity for discovery in their characters and within themselves. But the one constant? They will always be sisters.

Gun & Powder runs through February 23 at the Signature Theatre in Arlington, Virginia. Hear Pfeiffer and Raver-Lampman sing from the show in the video below: