In this mad world, you felt anything could happen. Out of the bed rose the Falstaff of one's dreams, hugely substantial despite the ravages of excess: Bryn Terfel bang on course to prove that this was the role he was born to play.
Did he seem in muted voice? Only for a moment. Then he was off, rising to the challenges with if not yet consummate ease then certainly the promise of it, once nerves have settled and he is worked in. As the set revealed its secrets - never upstaging the action with its trickery - he and his co-inebriates hatched their clumsy plot.
The director, Graham Vick, is a fabled loose cannon, and his designer, Paul Brown, is famed for his invention: the universe they conjured up was both outrageous and perfectly apposite. Ford's Garden was an undulating sea in which box trees rose as if by magic, the ideal place for trysts and deceptions. The bedroom unfolded from the heavens as though from the hands of a conjuror: the new House's problematic technology worked like a dream and was given the applause it deserved.
While Bernard Haitink created a kaleidoscope of string colour in the pit, the action bowled along unstoppably above. Roberto Frontali, as Ford, was a man as in love with his jealousy as Falstaff was with his paunch: his nightmare aria, reinforced by nightmarish lighting, was a beautifully sung tragi-comedy in itself. Bernadette Manca di Nissa made a sumptuously dark-toned Mistress Quickly, and Barbara Frittoli a gracefully expressive Mistress Ford. The crowd scenes - complete with tumblers - were deftly handled; the acting was uniformly convincing.
Although the final effect misfired, the last act was a steadily growing visual feast in which a drunk's-eye view of the world alternated with unadulterated beauty. Frittoli's aria in the enchanted wood was an enchantment in itself.
It was, in some ways, exactly the triumph the embattled Royal Opera House needed: it would have been a crime to junk it in favour of the Ligeti production we may now not see. The costumes on stage were bandbox-bright medievalism; friends of the House will be delighted to learn that the costumes off stage were of the traditional sort, with nary a smelly trainer in sight.