Sherlock is as you would imagine he would be as a teenager, but with more heart and surprising emotional understanding. I personally loved Mycroft's character, appearing out of nowhere, mostly at every dark turn Moriarty is about to take, and accomplishing everything asked of him effortlessly. Bravo!
Also, Watson is a side character. Ha! Not a very long book either, so when I could not put it down, it did not take to long to finish it. Great storyline, great characters, I am ready to read the next; so, be prepared for another Lock and Mori review in the near future!