Let’s just say art is imitating life. “On stage,” an introduction to the Finnish National Opera’s first post-pandemic-lockdown production tells us, “singers are rehearsing Die Walküre, when they are suddenly interrupted. As management has been laid off and the news of a global virus spreads rapidly, the Wagnerians are suddenly instructed to perform a modern satire on the situation.” Thus it is that two hefty sopranos whom the company in fact had under contract for the heavyweight parts of Sieglinde and Brünnhilde, wind up flouncing around as the flighty sisters Fiordiligi and Dorabella in Mozart’s exquisitely calibrated Così fan tutte, whose music they can’t sing, while a heroic baritone thrillingly cast as the Norse god Wotan attempts the cynical philosopher Don Alfonso, whose music he can’t sing well. Sophomoric political sketches (in Finnish, with English subtitles) edge out most of Mozart’s original partner-swapping scenario. Like the virus that begot it, Covid fan tutte is a sorry affair. For cosmopolitan cachet, there’s the ageless Karita Mattila, once an incandescent Fiordiligi, now scoring kamikaze self-parody as Despina, a ladies’ maid here transformed into a platinum-blonde pole-dancing granny who’ll be damned if she’ll stayed cooped up at home. But the singing you won’t forget comes from Tuomas Katajala, a frisky tenor whose joyous timbre, vibrant projection, and unforced elegance of line are like sunshine on a cloudy day. If there’s a Mozart tenor at large who can touch Katajala nowadays, he’s not on our radar. Turns out he sings lighter Wagner roles, as well, at the same exceptional level. —M.G.