Radio Times

• Episode 1/10

  The team are sent undercover in Iran when they receive intelligence that suspected terrorist Mehan Asnik is plotting a bomb attack on London. Their aim is to blow up Asnik in Tehran, making it look like a terrorist attack, but just as the team are about to detonate the charge, a train packed with civilians pulls up yards from the target. With the operation at a critical stage, the team must make a split-second decision that could cost many innocent lives.

  RT Choice (Alison Graham, 16 October 2007)

  This terrific series returns for its sixth outing. I love Spooks. It's fast, glossy, tightly acted, written and directed, and it makes a splendid virtue out of taking itself tremendously seriously. The opening story is a typically tense and complex affair that grabs you by the throat and refuses to let go.

• Episode 2/10

  With Britain facing a deadly plague, Harry rounds up key spies from nations likely to be involved in the plot, and begins an interrogation that he hopes will lead him to the vaccine. But these are some of the world's most hardened characters and they are going to need a lot of persuading. Ruthless agent Connie James is charged with obtaining the information, and what better weapon to use against her captives than the threat of infecting them with the virus itself?

  RT Choice (Alison Graham, 23 October 2007)

  I've never been a fan of Outbreak-style dramas where pasty-faced extras stumble around pavements, coughing up fake blood. Such plots are predictable inasmuch as you just know things will always turn out all right in the end after the inevitable cuticle-chewing race to find an antidote/vaccine. Which is exactly what happens here. But it's still tense and exciting, if almost insanely convoluted (I must admit, I got a bit lost). And, such niggles aside, Spooks is still the best drama currently on the box.

• Episode 3/10

  Zaf is still missing and his colleagues assume the worst, but a plane crash near an American air base shifts attention to the possibility of an Iranian offensive. Malcolm is sent to shoot secret footage of the Americans as they hastily clear the site and remove the wreckage to their base. Meanwhile, Roz refuses to yield as her kidnappers subject her to sustained mental torture.

  RT Choice (Alison Graham, 30 October 2007)

  Spooks is always good at giving viewers the visual equivalent of a face slap with some great set pieces, and the opening minutes of [this] episode are packed with skin-tingling incident.

  The plot is wildly complicated, as usual, but there's no time to become bored, or even to say to yourself, "Hang on a minute, can we just back up and go over that again?" Best just surrender to a delirious, edgy ride.

• Episode 4/10

  Despite Ros's reservations, Adam is still working Ana, his source at the Iranian embassy. With rumours that Algerian terrorist Abdul Kharami is planning an attack on London, Adam pressures Ana to spy on her husband, the Iranian special consul Dariush Bakhshi, who is suspected of having links to Kharami. Meanwhile, Jo is sent to find out who or what Kharami's target could be.

• Episode 5/10

  Despite Ros's reservations, Adam is still working Ana, his source at the Iranian embassy. With rumours that Algerian terrorist Abdul Kharami is planning an attack on London, Adam pressures Ana to spy on her husband, the Iranian special consul Dariush Bakhshi, who is suspected of having links to Kharami. Meanwhile, Jo is sent to find out who or what Kharami's target could be.

• Episode 6/10

  Ros and Adam are ordered to board a flight bound for Iran and recover a circuit board that is being smuggled out of the country. Going under cover as an air hostess and a passenger, the pair make swift, discreet searches of luggage belonging to those most likely to be carrying the board. Back at headquarters, Harry realises the office must be bugged and authorises a sweep of the Grid.

  RT Choice (Alison Graham, 20 November 2007)

  It's a terrific, exciting episode with a nail-chewing finale.

• Episode 7/10

  A tentative pact between Iran, the US and the UK has been agreed that could pull the trio back from the brink of conflict. A live television broadcast is arranged to announce the new peace and Ros exerts pressure on Iranian Special Consul Bakhshi to appear, using his wife Ana as leverage. But just as the programme begins, gunmen burst into the studio and demand that transmission be stopped.

  RT Choice (Alison Graham, 27 November 2007)

  In a tense but quite ridiculous story, Adam and Ros set about saving the day.

• Episode 8/10

  Ros has been found out by Bob Hogan and has no choice but to tell Harry about her association with Yalta. In a bid to redeem herself she offers to get information on Yalta's latest operation against America. This involves getting inside Yalta's HQ and taking Adam with her, but Yalta already suspect Ros's cover has been blown and taking her hostage, demand she reveals Harry's whereabouts.

• Episode 9/10

  The US military is preparing for air-strikes on Iranian nuclear facilities but back in London, Harry's team have been suspended from the Grid in the wake of revelations about Ros. Meanwhile, an old enemy from Harry's past informs the team that he has planted a bomb in central London. The team have to act to save the lives of hundreds of innocent civilians, but who is really behind the threat?

• Episode 10/10

  The Venezuelan President is being targeted by a CIA hitman, Annibal Rodriguez, and the Venezuelan secret police are offering intelligence on a planned al-Qaeda attack on a British school if MI5 intervene. Meanwhile, Jo is kidnapped by a group called the Red-backs who torture and kill spies. Adam asks Bob Hogan to help with her rescue but when Adam is also taken prisoner, he makes a shocking discovery about the CIA man.

Go to Series seven