I had someone hold the flash for me on this (high and left), but it would work in a similar way with on cam flash.
ISO 320, F7.1, Shutterspeed anywhere from 1/20th - 2 seconds depending on the effect you want.
The longer the shutterspeed the more light you let in from the background so you can get some pretty funky effects with this approach if you go for a long exposure particularly if there are room lights in the background. The flash will always 'freeze' your subject if you're in a relatively dark environment. This technique is all about livening up the background and giving the shot more life.
This exposure was about 1/2 a second. Enough to leave some movement in there but not too much.
Try it, just make sure you're in a relatively dark room!Happy Birthday James.