As always, the balancing act of the ensemble cast is present here. Kitty, Frank, Franco, Mr Grove and Mr Crabb all take a relative back seat this week, allowing other characters and their storylines to flourish.

Polly Walker’s Delphine Day is finally exposed to be after Harry, as we had previously suspected. Given that the Selfridge’s marriage seems back on track, it’ll be interesting to see where this development goes.

Walker is particularly effective in the ice cool yet two-faced Delphine, but this week saw that generally nuanced performance expanded upon. Singer Alfie Boe’s inclusion could have seemed like stunt casting, but his singing showman is both necessary to the storyline of the week and gives a necessary insight into Lady Mae’s character, allowing Katherine Kelly to shine with emotion and fragility.

Victor and Agnes’s relationship moves along at a quickened pace, heightened by Victor’s nationality and Agnes’s apparent friction with Henri. Henri himself is subject to a greater analysis this week too, with Gregory Fitoussi doing a grand job of playing him as aloof and enigmatic, without necessary losing sympathy. Similarly, Cal Macaninch’s Mr Thackeray, in the shadows in the early episodes, gets some welcome screen time.

The continuation of the themes of war are a common thread in this episode with Selfridges no longer selling German goods, the stores ‘Patriotic Concert’ and the shadowy recruitment of Harry for some as yet unknown European venture in the name of the British Government. Even something as simple as Franco being refused a date with a shop-girl whose father doesn’t want her ‘to see foreign boys’ showcases how entrenched in war the show has become.

It does provide drama on many levels from the grander (Henri’s arrest for spying) to the more subtle (Mr Grove’s implied jealousy towards Miss Mardle’s male Belgian houseguest) and is all the better for it. Kate Brooke’s script, and indeed Lawrence Till’s direction, getting the most from the wartime elements and the actors involved.

Of course, the episode belongs to Jeremy Piven as Harry. Wanting to do his part for Britain, Harry agrees to work on some secretive Government mission, but one can’t help but think this is the wrong move for Harry.

That he lies to Rose about the trip’s agenda and, at least in part, agrees to it from Lord Loxley questioning his integrity, showcases the rashness of his decision. And whilst it will no doubt continue the effective drama of the show, its characters and draw the best from Piven as a performer, the episode’s closing montage, sombre and dark, speaks volumes about the forthcoming repercussions of this decision.

Aired at 9pm on Sunday 23 February 2014 on ITV.

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