It’s getting personal, very personal, as the Gavrik plot arc begins to unravel in the penultimate episode of Spooks.

After Harry’s threat to CIA man Jim Coaver last week, the good guys are going after the bad guys. But just who are the bad guys? Come to think of it, who are the good guys?

Everything falls into shades of grey this week, as our spies fly in the face of the law, first by kidnapping Coaver, and then by infiltrating the American Embassy to steal evidence. But if only it were that straightforward. The web of the Gavrik plot is more tangled than we may have suspected: secrets of the Cold War are surfacing, relationships are at breaking point, and the lines of allegiance aren’t just being blurred, they’re being blown apart.

Pulses are set racing early on with a stunning car chase sequence through the streets of London, but in this episode it’s not the action that leaves an impression on you, it’s the quieter moments. The awkward conversations and things left unsaid.

In the best of these, Harry Pearce and Ilya Gavrik share a scene dripping with subtext, forcing the audience to re-evaluate how we see our top man on the Grid (and it also may just have you wondering why you don’t own a tortoise). Peter Firth and Jonathan Hyde are mesmerising as two old relics of the Cold War facing off, still uncomfortable with one another’s presence, whether it’s under the glare of the government or just in a front room sharing a vodka.

Given the tension between the Russians, the UK and the US throughout the series it’s unsurprising that this episode has a very Cold War feel about it: rendezvous held in safe houses, underground car parks and mysterious rooms; people being asked to do things on the quiet; an air of secrecy and mistrust among everyone on both sides. You wouldn’t be surprised if George Smiley popped up in the Grid to share a smoke.

The Gavrik storyline may have been slow to kick in, but in taking its time to unwind it’s shown itself to be one of Spooks’ more intricate plot arcs, sharing the paranoia of old school spying.

Special mention also has to go to Nicola Walker who, as Ruth, does the best ‘worried face’ in the business, and in this episode more than usual. In her new role as Security Adviser to the Home Secretary (the extremely underrated Simon Russell Beale) she’s caught between loyalties to her former and current employers and balances the two on a knife-edge.

In the end though, it’s all about Sir Harry Pearce, a man who’s starting to wear his pain and aggression on his sleeve. Series 10 has managed to give new depth to Harry, quite a feat for a decade-old character. Having been personally compromised from the start, he’s made some questionable choices and now he’s marching toward his fate like a good soldier; confronting a troubled past and an even more troubling future.

With just one episode to go after this, it’s going to be fascinating to see how everything is going to be resolved and whether everyone is going to make it through to the end alive. At this point only one thing is certain: it’s going to be one helluva send-off for Spooks.

Airs at 9pm on Sunday 16th October 2011 on BBC One.

> Order the Series 10 boxset on Amazon.

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