Creating drama in a portrait can be easily achieved with as little as one light, but for this portrait, let's define some facial features with a rim light.
Using two speedlights modified with Rogue FlashBender 2 XL Pro Lighting Systems set up as gridded strips, we can focus the light in a very specific area. Using a strip gives us a soft but narrow beam of light, the grid enhances that focus even more while still keeping the softer quality of light.
Our rim light will be set up behind the subject on camera-left. Because of the use of a Strip Grid we're going to get light only falling on the side of head and hair. The grid prevents light from falling onto the background or bleeding too much into the lens and giving us lens flare effects.
Our main light will be set up opposite of the rim light, on camera-right. The use of a strip grid here is to focus the light on just our subject's face and create dramatic shadows that carve out his facial features.
Remember that posing is just as important in a setup like this, as moving the subject's face could result in undesired or different lighting patterns on his face. The more he moves his face away from the rim light, the more dramatic the image becomes.
With a simple background, two speedlights, and some Rogue modifiers we've achieved a dramatic portrait by defining facial features and posing our subject.
Resulting Image:
Camera Settings: 85mm Lens @ 85MM, ISO 100, 1/125, f/8