There is no such thing as a "typical" Karen Stephens part. Like the best actors anywhere, she's an invisible conduit for a playwright's unique creation, which, paradoxically, we cannot imagine existing without her. Thus, if Christopher Demos-Brown's world-premiere play Fear Up Harsh, which debuted in Miami courtesy of Zoetic Stage, receives productions elsewhere, Stephens' masterly lead performance sets a seemingly untouchable benchmark. Her lesbian army corporal — physically and emotionally bruised, desperate, and probably alcoholic — is as convincing a portrayal of a military veteran as we've seen onstage, with Stephens infusing her character's tortured memories and wry wit with lived-in intelligence. A few months later, she flawlessly inhabited another complex character — a brash, funny, Southern-bred maid with a heavenly secret — in GableStage's The Mountaintop. That secret torpedoed an otherwise provocative piece, but Stephens remained truthful even during its descent, culminating in a powerful soliloquy encompassing the past 40 years of African-American history that ebbed and flowed with the oratorical gusto of The Mountaintop's immortal subject, Martin Luther King Jr.