Sherlock Holmes : such an attractive smackhead...

Sherlock is uncommon in many a way: 

He is able to focus his superior mind on certain topics, all related to crimes, and display genial deductions; at the same time, he is completely ignorant in other fields, because he doesn't care and doesn't want to waste intellectual resources on it. That enough makes him more than an eccentric, a "freak". 

But the most frightening fact about him is his apparent lack of interest in any social activities, supposed to stir positive emotions : love, pleasures -common ones, at least... Sherlock seems far above all that is essential for "normal people".

Virgin of life ?

Jim Moriarty calls Sherlock “the virgin”. Obviously, Sherlock is far from being a womaniser, and doesn't seem very interested in human relationships anyway. Maybe is that the genuine sense of “virgin”. “You don't  know human nature, do you ?”, says Mary. Sherlock's friends see the child in him, the child he is still when it comes to affective matters. Isolated as a boy, just like Mycroft was, Sherlock seldom experimented social exchanges. He developed amazing deduction capacities, but lacks of affective ones.

Every relationship implies to take a risk, and sometimes to lose control. Sherlock does not take that kind of risk. He knows murderers better than lovers. He is able to build elaborated patterns with facts, but lacks of intuition.

A (high-functioning) sociopath, but not with John Watson.

“Freak”, “psychopath” is the image Sherlock gives. Mycroft is worst : he lives in a word of goldfish and despises them. But a miracle happens to Sherlock. He has no friend but one. So why John Watson ?

Probably because John doesn't fear him. First curious about such an uncommon gentleman, John soon becomes fascinated by Sherlock, who is flattered, of course. Despite rebukes, abrupt summons to perform absurd tasks, peaks of pride, crises of depression (when boring), unfair reproaches, unwilling victim of experiments, mess in the flat and heads in the fridge, and high-pitched violin compositions, John simply stays at Sherlock's side. 

He is addicted to action, clearly, and Sherlock is the best provider for it. But there is more than this. Sherlock has built a field of mines around him, protecting himself from any emotional exchange. John is the only one who dare to go through all defenses, just as if they simply didn't exist.

Benedict Cumberbatch, Sherlock reborn

The success of this particular adaptation is of course partly to be credited to the actors. 

And other actors also performed amazing Sherlocks before, no doubt.

But Benedict Cumberbatch is close to perfection. He is able to play a character built on pure logic without being Captain Spoke. Sherlock affects no to care about other people, but the actor shows a subtle sensibility through the character. Annoying, hopeless, his Sherlock is also moving, charming, and funny.

Besides, his ability to mouth so many intelligible words so fast is astonishing! In “the hound in Baskerville”, about 320 words (more or less) in 1 Mn and 10 sec ! Try to do the same...