"After some initial scepticism that the '24' style continuous story arc would become over-convoluted, I'm drawn into the whole Doomsday/crisis scenario as it unfolds.

Connie's a great asset - Sir Harry needs someone to keep him in check now that Juliet's gone. There's still a gap that only Ruth can fill."

Liz, Nottingham

"What I liked about this episode was its more natural, realistic style - emotionally involving but still managing to remain suitably detached. Rupert Penry-Jones excelled himself again as Adam, battling to save Jo. The whole show was a scintillating mix of suspense and emotion.

The outside-London scenes gave the episode a more urban tone, which made it more plausible than usual, whilst remaining exciting and tense.

However, Spooks is unfortunately beginning to suffer from the absence of the inimitable Raza Jaffrey. I hope this excruciatingly nerve-wracking storyline can soon be resolved."

Natalie, Beckenham

"I'm starting to feel that this once excellent series has given in to James Bond style and last-minute action to save the world. The storylines are beginning to stretch credibility, designed to create a major big moment rather than reality."

Mark Stacey, Worcester