At this point the play, having had its comic face slapped, means to turn the other cheek. In truth, it’s about time; with no conflict to propel it, it has been fueling itself for too long on whimsy. (Dr. Wally, a bumbler who mixes up his patients’ names, seems like a character straight out of vaudeville.) Now Bessie must call her sister, Lee, whom she has not seen since their father’s first stroke two decades earlier. Perhaps Lee (Ms. Garofalo) or one of her two sons (Jack DiFalco and Luca Padovan) will be a bone-marrow match.
From then on “Marvin’s Room” concerns itself with the deeper questions of caretaking: Is it selfless or — as Hank, Lee’s troubled 17-year-old, maintains — just another kind of selfishness to devote oneself to others? (“People don’t just do things,” he says. “They get something for it.”) Piling on, Lee, who is tough and wayward and casually abusive, points out that if Bessie is glad to have stayed with their father and aunt, why should Lee feel guilty about having left her to do so?
As the play pauses to consider these thorny questions, offering variations on the theme of guardianship and neglect, the plot gets a case of the doldrums. Bessie especially becomes becalmed; her illness only burnishes her halo as she adds her sister and nephews to the roster of relatives she can help. It is a relief, and the story’s most touching moment, when Lee finally does something for Bessie instead: A budding cosmetologist, she offers to restyle her wig.
If in 2017 the play seems to be stacking the deck, offering so many kinds of sickness needing so much care, there is a perfectly good 1991 reason for it: AIDS. Mr. McPherson did not have the disease when he wrote “Marvin’s Room”; it was based more on memories of Florida relatives in fact named Marvin, Bessie and Ruth. Still, AIDS was all around him. His companion, Daniel Sotomayor, died of it in early 1992, during…