Sherlock. The whole thing is so beautifully conceived, right from the initial idea that John Watson is a doctor invalided out of the war in Afghanistan, something that worked in both periods.
It's simply one of the best things on TV at the moment.
Yet excellent though it is, it does highlight for me a real flaw in the original concept that still plays through today. At the end of the second episode, Professor Moriarty ruthlessly executes a criminal who has let Holmes beat her. Even though she is sitting in a secure location, he effortlessly kills her. Yet somehow, despite the fact Holmes repeatedly thwarts him, he finds it difficult to bump off our hero. The fact is, the same technique as used at the end of episode two would shut down the whole business in an instant. I know Conan Doyle had to have Holmes escape Moriarty's fiendish attempts to kill him to keep the story going, but it really stretches the suspension of disbelief to breaking point that he couldn't be taken out by a sniper at any point.
Still, I'm enjoying it enough to be able to tuck that away and forget it... and looking forward to the new Series 2 episodes, coming soon.