Dans lighting is sublime. Beyond the obvious nod to classical painted portraits (and Dutch Masters in particular), he asserts a ridiculous amount of control over his illumination.
After watching the recent behind-the-scenes video of his shoot with Benedict Cumberbatch, I noticed that he makes great use of flags to attenuate light falloff on his subjects. I also noticed that he appeears to use a ringflash to provide on-axis fill flash as well.
So I fired up Blender and re-visited my earlier work on using it to visualize lighting setups.
I setup a small-ish softbox as a key light, and attenuated it with a flag, and placed a simple ring flash on low power to fill in the shadows of the subject. Here is my quick setup result: