Hospital waiting rooms are queasy yet strangely intimate spaces that have a way of whittling away pretense and revealing a person’s true self. Relationships with strangers can feel significant. Sensitive information about bodies is routinely, almost blithely, discussed. Gracie Gardner makes use of this fraught setting in I’m Revolting, which takes place in the waiting area of a skin-cancer clinic in New York City in 2019. Under Knud Adams’s direction, the play has flashes of excellence but never fully coheres or figures out what story, exactly, it is telling.