Even with her back to the audience, Alexis J. Rogers commands attention. Clad in a luminous white tea-length off-the-shoulder gown, Rogers channels Billie Holiday waiting in the closet-sized green room at Emerson’s Bar and Grill, the titular Philadelphia club in Porchlight Music Theatre’s wholly engrossing production of Lady Day at Emerson’s Bar and Grill.

As she wearily prepares to make her entrance, a three-piece band vamps through a jazzy riff that evokes the glamour and grit of late nights and intimate clubs. It’s a sound that can be as upbeat as a gin fizz or as mournful as a broken heart on a rainy night. Directed by Robert Lindley with musical direction by Jaret Landon, Lady Day at Emerson’s Bar and Grill is filled with such conflicts. It is both elegy and communion, a musical journey that will have you tapping your toes one moment and on the verge of tears the next.

At the deeply conflicted nexus of this retro-hued musical alchemy is Rogers, who embodies a woman struggling between her personal demons and public image. Rogers, who earned numerous accolades for her turn as Bess in Court Theatre's Porgy and Bess in 2011, creates an uncannily authentic portrait of the late, great vocalist, even before she starts singing. This is a study of layered contrasts: Rogers’ posture and face at once reflect steely resolve, profane defiance, and irreverent exuberance. She’s triumphant and tragic, a free spirit and slave to heroin. She’s also drop dead gorgeous, except those purple green bruises blooming around the track marks in her left arm.

But for all the visual depth Rogers brings to Holiday, Lanie Robertson’s script, a “musical biography,” drags a bit during the biography portions. In the exposition, Holiday’s life remains a skeletal outline, when in-depth examination would bring more depth to the story. What works to great effect is Rogers’ slow, steady unraveling as she moves through the play’s 14 songs. Lady Day is set shortly before the singer’s death in 1959, and about two-thirds of the way through Rogers’s performance, she steps backstage to shoot up, returning in a woozy calm.

How would Holiday fare in today’s era superstars like Beyonce and Mariah? She helped lay the groundwork for them, but she might not be able to keep up. The legacy she left, however, is captured in all its conflicted beauty in Lady Day at Emerson’s Bar and Grill.

Catey Sullivan is the contributing theatre critic for Chicago magazine.