This modern version of Sherlock has been well crafted and edited with a perfect cast. Benedict Cumberbatch plays Sherlock and does a stunning job with it as does Martin Freeman with John Watson. It's more like three movies than episodes as it has been edited and put together like a masterpiece.
Each episode is based on one of Arthur Conan Doyle's Sherlock stories. A Study in Pink is based on A Study in Scarlet, The Blind Bank is based on two stories called The Valley of Fear and The Dancing Men, while The Great Game is reflected upon a number of stories but mainly The Adventure of the Bruce-Partington Plans.
It's quite interesting to see how they changed the original story to fit into modern times, for example; John Watson keeps a blog instead of a journal.
By far Sherlock is one of the best television shows I have ever seen and is a perfect series and a perfect buy.