The Secret Agent ends, not with a bang (that was last week), nor with a whimper. It just sort of rolls to a halt.

Not that it isn’t interesting to watch it roll, but there’s no grand conclusion, no big finale. In keeping with its theme of the circle – perpetuated in clock faces, Petri dishes, Stevie’s drawings, and even the blast crater that he left behind – there isn’t really an end. The big wheels of politics and conspiracy keep on turning, and the little players like Verloc and his family are ground under them. If you accept that then a mediocre finale becomes easier to reconcile with

After meandering around last week Verloc finally summons up the spuds and returns to tell Winnie a truth she already knows. Like Winnie we watch, silently, as he verbally flails around, trying to pin the blame on everyone, anyone, but himself. Inspector Heat, Stevie, the Russians, even Winnie herself. The more he flusters and blusters the worse it gets for him. It’s a great performance from Toby Jones, an actor who’s never afraid to really get under the skin of an unappealing character.

Jones has all the words but it’s Vicky McClure who steals the attention throughout, and all by saying nothing. She’s silent, still for so long. And then when she does say something it’s alarmingly concise and composed. For a quarter of an hour you’re just waiting for her to explode.

But she doesn’t explode. Explosions are messy, unfocused. We saw that in Episode 2. No. She’s deadly precise in her response. She stabs him to death and in doing so shows greater calm, premeditation, and determination than Verloc ever did in trying to commit his act.

Here though is where things begin to tail off, and The Secret Agent‘s final episode loses the momentum of its thrilling first 20 minutes. Winnie flees to the barely-there character Ossipon (Raphael Acloque), a man who we’ve had about ten minutes total of screen time with over the past two hours, much of which was flirting with Winnie with all the subtlety of a Sid James guffaw. Yes, she’s desperate to evade the noose and he’s a man with functioning genitalia and access to train tickets, but it’s hard to buy their closeness when we’ve barely seen any of it.

It doesn’t help that their flight from the law borders on the absurd: Winnie’s lie to the policeman at the train station is the most incredulous fib to a member of the constabulary since Mr Toad dressed up as a washerwoman. And when Inspector Heat catches up with them it’s all something and nothing; apparently in the 1800s a good speech is all you need to satisfy the Law and get away with murder.

And just when it looks like Winnie’s finally struck a break, Comrade Cad himself, Ossipon, abandons her. He’s off to be the new Verloc. One who’s a double-agent for the police. The cogs of political intrigue keep on grinding. In the background, probably while Countryfile‘s on next week.

Alone, adrift, bereft and bereaved, Winnie throws herself into the sea, in an act that feels inevitable simply because she’s got no one else in the cast to interact with. And with her body sinking to the bottom of the Channel, The Secret Agent ends. An unhappily ever after for everyone. Given that this is a one hundred year old story that’s still alarmingly reflective of the current socio-political climate we’re enduring, that’s not so much a surprise as a reminder of the times we live in.

Perpetually grim, sporadically excellent, but never quite making enough of its cast or the source material to become the kind of ‘must see, must talk about’ TV we all crave, The Secret Agent has been just good enough for those with the patience for a slower drama on a Sunday. Still, unlike it’s protagonist, at least it didn’t bomb.

Aired at 9pm on Sunday 31 July 2016 on BBC One.

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