Spooks proves that it still has the capacity to shock in this thrilling follow-up to last week’s series opener.

When a suitcase destined for MI6 containing information regarding five key operatives is stolen, the team at Thames House are forced into a race against time. Desperate to find out who is responsible for stealing the case, they must also contend with the fact that whoever stole the suitcase is also leaking the identity of the agents to the press, compromising their cover.

Though it isn’t unfamiliar turf for Spooks, this race-against-time story model works well in sustaining viewer excitement and interest through the first 20 minutes of the episode, with particularly memorable moments including the scene where Calum and Dimitri are forced to disguise a murder as a suicide attempt, as well as the masterfully tense sequence where Martha Ford attempts to escape Gavrik after her identity has been compromised.

The resolution of the main plot, where it is revealed that the person leaking the encrypted information is just a disgruntled ex-MI5 operative, is admittedly slightly disappointing, but the mystery regarding just who delivered the suitcase to him manages to salvage the main plot from complete irrelevance.

Though this week’s story doesn’t deal with the ongoing Anglo-Russian narrative thread to quite the same extent as Episode 1, the revelation that Sasha Gavrik (Tom Weston-Jones) is in fact Harry Pearce’s son is touched upon. The sequence where Sasha murders a fellow operative to protect his mother, whilst Elena Gavrik tells Harry that his son is “like you, in some ways”, is a particularly poignant. Other than this scene, however, the ongoing subplot involving Elena and Sasha doesn’t really move forward and is probably the least interesting aspect of this otherwise excellent episode.

The sequences involving Erin Watts and Martha Ford, on the other hand, are the arguable highlight. Erin’s inner turmoil at the prospect of betraying someone not once, but twice, is heartbreakingly evident in Lara Pulver’s portrayal of the character.

It was also welcome to learn a bit about Tariq’s back story, conveniently before he is murdered in cold blood, otherwise the brutal closing moments would have carried little emotional weight. Really we should have guessed from the beginning of the series that Tariq was going to be killed off, when a new IT expert was drafted into the team (not to mention Tariq being conspicuously absent from the Series 10 cast promo pic), but despite all the signs, the cliffhanger at the end of the episode still came as a huge surprise to us.

The closing moments were shocking and brilliant in equal measure, but just who is the person that delivered the suitcase? It looked like it could be Elena Gavrik from the CCTV footage, which really would be an impactful twist; but maybe it’s someone else? Perhaps a returning character? One thing’s for sure, we can’t wait until next week’s instalment.

Aired at 9pm on Sunday 25th September 2011 on BBC One.

> Order the Series 10 boxset on Amazon.

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