“Those two,” the composer Pascal Dusapin calls the main characters of his world premiere, billed as “a bloodstained gothic opera.” Yes, we’re talking about everyone’s favorite ruthless climbers—the Macbeths. Commissioned by La Monnaie, Macbeth Underworld is directed by Thomas Jolly, with Alain Altinoglu conducting. Scheming couples never cease to amaze. —L.J.