The first step is to adjust the Levels (Image > Adjustment > Levels). Move the shadow slider inward until the picture is darker, but still has details in the shadows. Here, a setting of 43 worked for me.
Desaturate the image. Go to Hue/Saturation (Image > Adjustment > Hue/Saturation) and decrease the saturation to your liking. For me, a setting of -41 worked for this image. Notice that I said "for me" twice. My suggestion is to play around with the sliders to see how they affect your image. What works for me also may work for you, or you may prefer a lesser or greater effect. Next, adjust the Hue/Saturation (Image > Adjustment > Hue/Saturation).
Next, duplicate your layer (Layer > Duplicate Layer).
It's time to apply the High Pass filter (Filter > Other > High Pass) on the top layer. Leave the Radius at the default setting of 10 pixels. Your image will look weird. No worries. That will change soon!
In the Layers panel, select Overlay as the Blending mode. When you click and release, you'll have your more dramatic image. Next, flatten your image. Now you can use basic enhancements to fine-tune your picture. Make your picture darker or lighter, reduce or enhance contrast and/or color, and maybe even use the Dodge tool to whiten the eyes. The only enhancement I applied was Vignette (Filter > Lens Correction > Custom > Vignette) to draw more interest to the subject.
If you're looking for examples of dramatic photographs, check out the work of Yousuf Karsh. His famous portrait of Ernest Hemingway is one of the most dramatic portraits I've seen. It was taken on film and processed in the wet darkroom. It's Karsh's work that inspired me to create dramatic digital portraits.
Rick Sammon is a longtime friend of and writer for this magazine. Get to know him better at www.ricksammon.info.