The Bill:
Warm Bodies (Parts 1 & 2). Investigating seemingly separate incidents - an apparently deliberate hit and run and a brutal assault outside a nightclub - DS John Boulton and DS Claire Stanton soon begin to believe the crimes are connected, but their collaboration on the increasingly dangerous investigation has a somewhat unexpected side effect when their relationship begins to change from professional into something considerably more personal. But there's something about Claire Stanton that neither John nor anyone else at Sun Hill is aware of... This gripping 2 parter drops one hell of a dramatic bombshell on the audience, with the revelation that the quiet and unassuming Claire Stanton, who slipped unobtrusively into Sun Hill six months earlier, is actually an undercover CIB officer, planted at the station for the sole purpose of spying on, and gathering evidence of the corrupt activities of, one DS Don Beech. It's a fantastic, jaw-dropping twist, and one that serves notice that the long-simmering Beech corruption storyline is reaching boiling point...
Oh, and I love that the codename of Claire's (male) CIB contact/boss is "Mother", in a clear nod to 60s British cult spy series The Avengers!
