THE merchant’s wife gazed out of the window, troubled. “How strange,” she mused, “that we should be discussing a ball when we are on the brink of war. How ridiculous!”

Not at all, my dear. Everyone needs a little escapism and for many this latest work of galloping frippery from Julian “Downton Abbey” Fellowes, has not arrived a moment too soon.

Based on Fellowes’ novel of the same name, Belgravia opened in Brussels, 1915. Napoleon was on his way, society was all a flutter, and James Trenchard (Philip Glenister) was doing a roaring trade keeping the British troops supplied in food and ale.

Trenchard had wangled invitations to the Duchess of Richmond’s ball. His wife Anne (Tamsin Greig) feared the family, being from the mere middle classes, had no place at such a grand occasion. The Duchess (Diana Kent) agreed. “I’ve invited a merchant supplier to my ball!” she gasped on spying them.

As the Trenchard’s daughter Sophia danced the night away with a young aristocrat, Anne’s lips pursed ever tighter. Sure enough, when the young lord whispered to Sophia that they were the luckiest couple alive, you just knew trouble was coming down the tracks. So it proved when the story fast forwarded a couple of decades and we learned what had happened after the ball was over.

As with Downton Abbey, Belgravia is all about class and wealth: who has it, who doesn’t, and who wants it. Here, it is the grocers and the builders, the self-made men, who are on their way up, and the nobs don’t like it. Nor do the servants, judging by the gossip downstairs at the Trenchard’s home in Belgravia, “this spangled city for the rich” as another duchess calls it.

Belgravia is positively hoaching with duchesses, and terrific actresses. Greig and Harriet Walter, playing Lady Brockenhurst, are at the centre of the tale, two very different women united by a life-changing event.

Slyly humorous and nicely melodramatic, Belgravia is not quite Downton standard yet - Downton took a while to be Downton standard - but the signs are good.