2016–2019: Early work and Slave Play
Harris landed a role in the play Jon at the Steppenwolf Theatre Company. He worked as an actor in Chicago, then moved to Los Angeles to further his career. There he began a collaboration with musician Isabella Summers that resulted in the play Xander Xyst, Dragon 1; the play was produced at ANT Fest 2017 in New York. He had a residency at the MacDowell Colony, where he wrote the play "Daddy", in which a young black artist (Franklin) becomes involved with an older European art collector (Andre). "Daddy" served as Harris's writing sample when he applied to the Yale School of Drama, where he began studies in the fall of 2016.
At Yale, Harris wrote Slave Play, where it was produced in October 2017, and won the Lorraine Hansberry Playwriting Award and the Rosa Parks Playwriting Award at the 2018 American College Theatre Festival. Slave Play was then produced off-Broadway at the New York Theatre Workshop under the direction of Robert O'Hara in 2018, Harris's first professional production as playwright. The play addresses sexuality and racial trauma in America. It begins with interracial sexual violence on a slave plantation in the American South and continues in present-day America at a sex therapy retreat for interracial couples. The couples include black participants who are no longer able to receive pleasure from their white partners. The white partners have a blind-spot about the role that race plays in their relationships. Critic Jesse Green summarized the play's message by saying "that one race lives with history each day while another pretends not to". Though critically acclaimed, the play drew ire from those who found the play's content disrespectful of African-American history. For the 74th Tony Awards, Slave Play was nominated for a historic total of 12 awards. This broke the record previously set by the 2018 revival of Angels in America for most nominations for a non-musical play. Harris was the winner of the 2018 Paula Vogel Playwriting Award, given by the Vineyard Theatre in New York City. A profile in The New York Times said that Harris's "ability to render subconscious trauma into provocative theatrical expression, as potentially unsettling as entertaining, has earned him a lot of attention in a very short time." Out called him "the queer black savior the theater world needs".
In 2018, Harris was awarded the Paula Vogel Playwriting Award, which includes a residency at the off-Broadway Vineyard Theatre. In 2019, The New Group and the Vineyard Theatre co-produced a revised version of Harris's earlier play "Daddy". starring Alan Cumming. Reviewer Christian Lewis called the play "a bold, experimental, political, and important work of theater that will not soon be forgotten". New York Times reviewer Ben Brantley noted some excellent performances, but found the dialogue "endless and circular and repetitive" and the play too "cerebral". In November 2019, an experimental work entitled Black Exhibition, credited under the pseudonym @GaryXXXFisher, debuted at the Brooklyn theater Bushwick Starr. Using Ntozake Shange's term choreopoem to describe its structure, Harris combines language and movement in a work that centers on five characters: San Francisco writer Gary Fisher, Kathy Acker, Yukio Mishima, Samuel R. Delany, and Missouri college athlete Michael L. Johnson. It was directed by Machel Ross.
