I started watching the recording half an hour after the broadcast started (was watching a recording of 'The Apprentice - why I fired them' first) and there was an interruption in the signal and so I missed the last ten minutes. I'm now watching in on ITV + 1.
I quite enjoyed it. The ending didn't bother me as sometimes guilty people do get away with their crimes, but, I do think it was set up so that another series is very possible.