This 1939 play is old-fashioned in the worst senses of the word: banal, predictable, corny. It’s what’s often called a gentle comedy, a phrase that here means entirely lacking in humor or drama. Paul Osborn’s account of a weekend in the life of four elderly sisters raises issues with dramatic potential–the road not taken, the regrets that accompany aging, family members’ collusion in creating myths and hiding the truth, the potential to mature deep into adulthood. But Osborn just skims over them, and he treats the over-60 protagonists as though they’d been lobotomized. In the nine-person cast, Roslyn Alexander and Robert Breuler stand out as the eldest sister and her husband, whose marriage seems the most endangered and turns out to be the soundest. But Jessica Thebus’s leaden direction dims even their work, and dooms that of the rest of the cast. Through 8/28: Tue-Thu 7:30 PM, Fri-Sat 8 PM, Sun 2:30 and 7 PM. Also 2:30 PM Sat. Drury Lane Theatre Water Tower Place, 175 E. Chestnut, 312-642-2000. $35-$48.