The Royal Opera’s Ring hasn’t had the easiest genesis. Cluttered with more symbols than the Highway Code, clobbered by most critics as its episodes were unveiled over the past three years, it also lost its most compelling performer when Bryn Terfel pulled out of singing Wotan very late in the day — apparently because his son broke a finger. It’s lucky that Wotan himself doesn’t behave so tenderly towards his offspring. Wagner would have lost half his plot.

So the omens seemed dark (as they say in Norse mythology) for the three complete Rings at Covent Garden this autumn. Yet on the basis of last night’s thrilling Rheingold, an unlikely triumph could be snatched from the jaws of scepticism.

For a start, Terfel’s replacement — John Tomlinson — is magnificent. He may be the wrong side of 60, which makes his duet about Freia’s apples of eternal youth with another durable British veteran, Philip Langridge (mercurial as Loge), particularly poignant. And these days the power in that famously baleful timbre may come and go. But Tomlinson is such a mesmerising figure, and he makes Wotan so intriguingly complex: capable of vile tricks, but also of being moved to tears by the sight of Alberich’s flayed victims.

Even his age works to his advantage. Here is a Wotan exhausted by the mission to build Valhalla, desperate to realise his vision, yet conscious that his powers are waning by the minute.

Keith Warner’s staging — much derided for mixing the homely (even the Rhinegold looks like a Christmas-tree bauble), the wacky and the cosmic — now seems to make a lot more sense too, at least to me. Think of the gods as a bewildered 19th-century aristocratic family, withering in their marble drawing-room in the face of menacing tradesmen (the giants), and forced to make a terrifying plunge into the future (Alberich’s horrific laboratory, with its dismembered corpses, zombie guards and Nazi-style experiments) in order to survive. Yes, Stefanos Lazaridis’s sets still seem crammed with far too many ladders, ramps, ropes, silhouettes and girders. But the revelation of Nibelheim — literally from the bowels of the earth — is a terrific coup de théatre.

Nevertheless, it was the musical values that most impressed last night. Peter Sidhom’s gleeful Alberich is every bit a match for Tomlinson’s Wotan, though his voice was tiring by the time he hurled out his curse. The Rhinemaidens (Sarah Fox, Heather Shipp and Sarah Castle) are an alluring trio, in and out of their Miss Marple outfits. Rosalind Plowright’s volatile Fricka is far more focused, vocally, than I was expecting. All down the line there are riveting performances.

And Antonio Pappano conducts with exemplary attention to detail, balance and blend. Occasionally — in the Giants’ music, for instance, or Nibelheim’s clangorous ostinatos — he could afford to let the orchestra off the leash. But to hear Wagner’s teeming scores so cleanly and rhapsodically delineated is riveting. Perhaps those who persist in declaring Warner’s staging to be crass should shut their eyes and let the music conjure up the drama.

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