So, this is it. The War has come to Downton, and Dame Maggie’s unique brand of hauteur is tested by ping pong in the Library. Whatever would the servants say?

Well, we know a little of what they’d say, because maid Ethel has got her eye on one of the officers and, according to the first rule of period drama, it cannot end well. Ethel may harbour dreams of being the new Mary Pickford or Pearl White, but as a flighty piece with Ideas Above Her Station™ there’s only one way she’s going to be humbled, and it’s certain to involve her being done wrong.

If only she had some of the nous of some of her social superiors, but they are a parliament of wily old birds at Downton, and they don’t take to a preening chiffchaff in their midst. Among them, O’Brien dresses like a jackdaw and wears the expression of a pall-bearer who has personally disemboweled the corpse.

But if there’s one thing writer Julian Fellowes is repeatedly keen to tell us it’s that, in wartime, compassion and sincerity are found in unexpected places. Thus it is O’Brien – she who had a brother with shellshock – who is most placed to offer comfort to the nightmare-tormented Lang.

It’s a nice sub-plot, and for a brief moment, it raises the possibility that O’Brien may have her heart thawed by the love of a good valet. But Downton plotting never works like this. Fellowes shuffles and reshuffles his deck of characters like a magician who’s forgotten the point of the trick. And so he obliges Lang to do the noble thing – as every character in Downton must Do The Noble Thing – and fall on his sword.

It’s fine. We’re not angry. We never expected a happy ending. But Downton Abbey has played this cat and mouse game with us so many times before that we no longer know what’s misdirection and what’s just saggy plotting. Outside the walls of Downton, the battle-scarred limp and beg. Inside, there are still moments of French & Saunders business about how best to apply curling tongs. One half expects Julie Walters to come tottering in with two soups, madam.

We know this because we’ve been here before. Some of us are still waiting for the homicide plot suggested by the confusion of brass polish and chopped egg in the first series. But Downton Abbey can be – should be – better than this.

When the soldiers first arrive at Downton, there’s a wonderful tracking shot which lasts for one minute and eight seconds without a cut, and takes in many of the principal characters as well as tens of extras. It’s a triumph of choreography and cinematography, and echoes a similar minute-long shot in the very first episode of Series 1, which tracked Daisy and Thomas through the house.

Such scenes tell us what millions of fans, ourselves included, know: that there is genuine mastery here, as well as characters we care about. Even at its clunkiest, Downton Abbey is still head and shoulders above the rest of television. It’s just that, with war in Europe and things literally now a matter of life and death, we had expected something a little more, well, urgent.

Aired at 9pm on Sunday 2nd October 2011 on ITV1.

> Order the Series 2 boxset on Amazon.

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