BBC Collateral review episode 3: ★★★★★

Having got off to a exciting and politically intriguing start, episode three of BBC Two’s Collateral stepped onto the pulpit and delivered a rather boring sermon. Where once was subtly, is now self-indulgent explanation and exposition. We're holding out hope for episode four.

Those who’ve read our reviews of episode one and two of playwright David Hare’s latest thriller, will know that behind the murder mystery story is a ‘state of the nation’ drama, come to make us blush about Britain’s moral bankruptcy. But, where episodes one and two toyed subtly with issues of homophobia and racism, episode three saw the cop drama become a bit too preachy.

So far, we've saluted Collateral's deft handling of political issues. We cheered on the show for it's female-heavy cast and the way a gay relationship between the Church of England vicar and an illegal immigrant (played by Kae Alexander - read our interview) was handled as though there wasn't anything unusual about it. We also fell in love with the faced-paced 'why dunnit' mystery at the heart of the show.

Predictably perhaps, the first episode split opinion down the political lines: The Times gave it two stars, The Guardian gave it four. The Daily Mail noted that Carey Mulligan ‘wraps up warm in chic coat and Burberry scarf’ at the Collateral screening. As expected.

Episode three saw our shooter Sandrine (Jeany Sparks) explain in one long monologue to her therapist how British foreign policy turned her into a murderer: 'last year, no British soldier died in action overseas, do you know when the last time that happened was?' before laboriously listing all the battlegrounds from the Falklands to Afghanistan.

Quick! Someone tell Mastermind we've found their most boring contestant. Sandrine missed out Northern Ireland though – which meant she could chastise herself for having forgotten it, and tell us that it was where her Dad had fought. If that was an attempt to add some personal into the GCSE history lesson, it didn't really work.

Local MP David Mars gets himself into political hot water by saying: 'can't we just say he was a human being, who was shot down on a British street? It doesn't matter where he came from', before adding, 'isn't it time we had an immigration policy that wasn't just crass xenophobia?'.

At one point we're even told: 'this isn't the best restaurant in the town but it is one of the nicest, because they have table clothes and proper napkins,' yes, thank you, we can see that. It's amazing the sentence wasn't followed up with: 'I'm wearing beige with pearls because I'm a small minded, emotionless English woman, darling'. Where was all the subtlety of the first episode?

The only excitement came from Billie Piper's over-blown, mug-smashing, drug-riddled hissy fit, KIP's successful but unlikely conversation with Fatima (Ahd Kamel) and Sandrine's appearance outside her Weinstein-like senior officer's house.

Fingers crossed episode four will mark a return to form, with less talk and more show. And hopefully a neat ending to tie up all the unravelling loose ends that are spinning out across the TV screen at us.