Sherlock returns for Season 4 in this January 2017 on the BBC. Sir Arthur Conan Doyle’s iconic detective has seen several incarnations on screen, and while we all might have our favourite, Benedict Cumberbatch’s take on the great detective is definitely right up there with the best.

But how did Cumberbatch develop his version of Sherlock? Apparently, it’s about understanding who he was before you meet him in Season One.

“Sherlock isn’t just Sherlock, he was a baby, then a child, then an adolescent, then a young adult, and then the 30 year old that you met in Series One Episode One. We know he’s got a brother called Mycroft and parents but what the hell was his childhood really like?” said Cumberbatch.

“I wanted to know all that information very early on because you’re playing the most adapted and greatest fictional detective of all time. You need to have a back story to work off as an actor because what are you doing other than emulating certain airs and graces and mannerisms. What I try to do is underpin all those decisions with an informed understanding of who my character is.”

Cumberbatch goes on to explain that while it might seem that way at times, Sherlock’s temperament is driven his own desire for perfection rather than the inadequacies of others.

“Oddly, I think Sherlock’s temperament is more shaped by the fact that he is human and trying to be superhuman. The amount of stuff that we call polite civilisation is a huge distraction to this man who has to think on an unparalled level of complexities. It’s not really that the world is stupid it’s just that for him to be clever he has to really drown out a lot of noise and what he permanently gets surprised by, and what I think is his real weakness, is sometimes not seeing what’s right in front of him.”

“His blind spot is the very thing that he purposely turns his head from in order to be as good as he is as a sleuth. So it’s a complex relationship he has with the world. He needs it to be that way in order to conquer it but at the same time the way he engages with it often blinds him to the most obvious. That’s great from a story point of view because people don’t see things because he doesn’t see them. His stupidity is also the world’s brilliance which is why there are things, people, and events, which overtake him. He’s not unhuman, he is human and he is fallible.”

In Season Four we’ll see a different side to Sherlock though. The self-labelled “high-functioning sociopath” will have to deal with a new addition to the cast. Where at first there was just Mary who’s come between him and John Watson, and that hurdle’s been… well, hurdled, along comes the newest addition to the Watson family.

The Watsons and Sherlock

“I think Sherlock feels very protective towards them as a family, but he’s not a natural or a figure of authority when it comes to a new-born. I hope my skills and interaction with my own are a little bit more engaged than his are! He’s seemingly indifferent which is comic at times but it’s all underpinned with a deep love and he’s a guardian angel really.”

While the dynamic between Sherlock and John will change, showrunner, Steven Moffat and the rest of the cast is confident that the bond is stronger than ever between the two best friends.

“It’s a very powerful friendship.  Now they don’t so much need each other as hugely enjoy spending time with each other.  They are best buddies and they’re having the best time solving crimes together, they love it.  At the beginning of series one they were two wounded beasts supporting each other, now at the beginning of series four they are at their best and the best of friends.”

“The thing about Sherlock Holmes is that he is a grown-up. We always like to pretend he’s an absolute lunatic but he does things well and he straightforwardly adores John and Mary, they’re his best friends.  So he behaves probably better than most young men behave when their best mates are having babies.  He’s pretty good at all that.”

Martin Freeman (Dr. John Watson), shares a similar opinion:

“The fact John is with Mary and ensconced in that life and not living at Baker Street anymore changes something in the relationship between John and Sherlock. It wouldn’t be much of a show if it changed it to the extent there was just that domestic life and all we were doing were feeding babies and changing nappies and then Sherlock is off fighting crime on his own,”

“It still has to be the same show so there has to be a bit of give and take.  Obviously when you get married and have a baby that trumps everything else in real life but for this show John and Sherlock’s friendship has to stay central so it will still be very John and Sherlock centric but the reality is that John has moved on as he did in Conan Doyle’s books – he moved out and had his own life slightly away from that.”

Sherlock returns for Season Four on the BBC on 1 January 2017. It’ll be available in Singapore on 2 January, from 7am (SG time), on BBC Player.