As soon as Series 5 was reaching its watery conclusion, the green light had already been shone on this next run of BBC One’s popular spy drama.

With Series 7 currently airing and the brand branching into spin-off territory with BBC Three’s recent Spooks: Code 9, it looks likely that some part of the Secret Service will always be represented in a BBC prime-time slot on one of its burgeoning channels. In a very similar to way to America’s CSI franchise, one can see many different permutations of this show knocking around for years to come.

Just as the show was taking a leaf out of American drama programming with multiple series, this tranche heralded a new departure with an attempt to pepper a common storyline through each of its 10 episodes. The MacGuffin here was a proposed peace deal between the UK and the Iranian governments, who had been hoodwinked by an American ploy to start a war with the Middle Eastern republic. Yet things get even more entwined between the two nations as the Chief of Section Adam Carter begins an affair with the Iranian Ambassador’s wife.

There is definitely something missing from this sixth outing and the oft critical comparisons to 24 are becoming ever more indefensible, with characters and storylines behaving increasingly erratically – behold the scene where Carter is tailing a potential mark outside a shop with an earpiece in full view and talking openly. As is common now, the closing episode of the series (and indeed the opening episode of the next) heralds the death of a major character, which has become so transparent as a plot device for this show that much of its intended impact is lost through ‘guess who’-style expectation.

Released on DVD on Monday 6th October 2008 by Contender Entertainment Group.