Not many ingenue playwrights get profiled in the New Yorker before their plays go up on Broadway. That’s so true it sounds insane; few young playwrights get their stuff anywhere near Broadway, period. Katori Hall, a few years ago at age thirty, got that treatment for The Mountaintop, a two-hander she wrote in honor of her mother, who as a teenager in Memphis was forced by her mother to miss Martin Luther King’s final “Mountaintop” speech. Feeling the ominous vibrations in the air, she kept her daughter home. As it turned out, of course, the young, black teenager would probably have been safe enough that night, but King was assassinated the next day.

In The Mountaintop, Hall writes her mother into history as a maid who brings King a cup of coffee at the Lorraine Motel after he gave that speech. Camae (her mother’s actual name) sashays into room 306, and instead of being awed by the great preacher and civil rights leader, she challenges him to every kind of moral, intellectual, and emotional duel–at one point, standing on the bed and wearing King’s jacket and shoes, she even out-preaches him.

The New Yorker profile of the playwright on a visit to her mother in Memphis is worth reading for its unspoken bittersweet message. Hall comes off as kind of a pill, but when she came of age, her fearless, provocative personality flew like a homing pigeon to where it still thrives: big-city, world-class theater. Before her play went up on Broadway (starring Samuel L. Jackson and Angela Bassett!), she was the darling of London’s West End, where she won the 2010 Olivier Award for Best New Play. That same personality, though, didn’t serve her mother so well in 1960s Memphis, or the following decades either, where she just couldn’t seem to catch a break in anything she did.

So how would Martin Luther King, or really any martyr, modern-day or historical, engage with a random stranger during his last hours? It’s a dirt-simple and astonishingly compelling premise for a play (I can hear creative writing teachers everywhere yelling ‘Yes! The only lesson plan I’ll ever need!’) And that, I’m afraid, is the last good thought I had about Hall’s play, which I caught in its current run at the Performance Network.

Beginning on a note that is intended to demythologize King, Hall whacks a few too many supports out from under him. Put her anxious, rabbity King in the ring with Willy Loman, and Loman wins the alpha male trophy. Casting doesn’t help here: King is played by fidgety, tenor-voiced Brian Marable, lately, and greatly, of Purple Rose’s Superior Donuts. Anyone could wipe the floor with his King, and dazzling Carollette Phillips as Camae does; then the limp battle-of-the-sexes comedy veers off in an entirely unexpected direction: Camae announces that she’s actually an angel and telephones God to ask for additional guidance. The Mountaintop has now landed in the middle of the Mitch Albom drama school. Honest to God, I never thought I’d say this, but Albom does it better.