This is an unusual angle, and it's so good! If you used a reference, I'm not recognizing it at all. Fun to be looking down at the top of Sherlock's head for once. Also, *maps*.
I especially like what you've done with light and shadow here. There's something so great about having the Thames go through his cheekbone. It brings light to that area, because it's not all smudgy with buildings. Great job!
I love it Great blending and colours, and I love how the map seems to expand outwards from Sherlock's head, very cool effect I like your shading style and the job you did on his hair, and his almost-mischievous expression is great! Love the pic