Spooks, the pacy MI5 thriller that has helped re-establish the BBC's reputation for contemporary drama, tonight returns in explosive, and potentially controversial, style. The fourth series opens with a two-part special based around a terrorist attack on London's transport network, which originally went into production last November.
Inevitably, the subject matter caused consternation after life imitated art on July 7. Although the fictional terrorists in question are not religous extremists, the similarities were sufficient to cause head of drama Jane Tranter and new BBC1 controller Peter Fincham to agonise over whether to drop the episodes.
But executive producerJane Featherstone, also managing director of production company Kudos, said that their decision showed the extent to which a drama holds a mirror up to society.
"We reach an audience that doesn't watch Newsnight or Panorama. It's not lecturing in any way and it's told through characters that are as flawed as we are and it will spark debate," she says.
Later episodes in the series will examine the threat posed by the far right in the current climate and issues around ID cards and freedom of speech through the introduction of Juliet Shaw, the national security coordinator, played by Anna Chancellor.
With its tendency to kill off major characters at brutally regular intervals, Spooks does not have to rely on a star. And with a team of writers and directors and regular guest appearances, such as Martine McCutcheon in this series, it is an ensemble piece.
"It's about loyalty to a brand," says Featherstone, adding its success is also down to the way it mixes the personal with the political. In the first episode of the new series, the characters are gathered at the funeral of their former colleague Danny when they hear about the bombs.
The scepticism of many of the best writers had been overcome, says Featherstone: "You can come in and write a play for us that reaches millions. The time of the two-parter is still here but we need to shift the balance towards authored series."
Featherstone argues that Spooks, and its sibling Hustle, have proved that a British team of writers can make intelligent dramas that are equal to US fare in scale. "It's not as though we don't have the talent," she says. "The biggest influence [on Spooks] has been on the pace and ambition of the storytelling. We are able to tell big scale stories that are quite personal and don't alienate the audience." With a fifth series already in production, she predicts it will continue. And Spooks has followed the US lead in another sense, she says: "We're not afraid to use people who can act but also look good. It's nothing to be ashamed of."