Lucky Joe in this photo was sandwiched between two lights, a rose between two thorns as it were. Simple to do, yet effective.
The light from behind (rim light) gives the portrait depth because it separates Joe from the darkness behind.
How to do it:
One bare flash on a stand more or less directly in front of the model, above the camera, at 1/4 power.
Another bare flash, on stand, directly behind the model, hidden from view by him, on full power.
Both triggered wirelessly, and there you go.
We were under a railway arch for this shot, so the background is nearly completely dark. This was enhanced by using f11 and a shutter speed of 1/200s which really cut down on the amount of ambient light hitting the sensor. Almost all of the light on the model is from the flashes. Obviously flash to subject distance and your flash power have an effect, so see what works best for you and your kit.
This shot is from our location lighting workshop.