Please disregard the comments that this is too dark. You are in great company. Please check out a few of the portraits at //www.ernst-haas.com/main.html. Particularly look at Haas' portrait of film director John Huston. If you can find it on the web, Haas also has a wonderful portrait of Leonard Bernstein that uses this lighting technique.
All you need is an ash tray on the desk with a lone cig, smoke wafting towards the ceiling. :) Come to think of it, that would have been an excellent additional element. Really like the strong side lighting. 8
The strongest aspect of this picture is the story it tells. The comp is superb. Foreground/background is stunning. You could have rendered in black & white but the colors drag the eye to just the right places. I'm glad you didn't. (10)
Great use of lighting to convey mood. I'd feel like the right figure was more natural if there was some kind of arm motion, but overall its well composed!
I'm intrigued by the narrative going on here, but there seems to be only one light source, and it's too extreme to one side. If feels like there's too much black, and I'd like to see a bit more of the figures. It took me a second look to make them out.