The background was made from 5 exposures merged as HDR . Model taken from best exposed still. Walls taken back to as dark as could be retaining detail. Window given a little More light to look more light than grey. High ISO 3200 used so that the model would be clear – natural light with reflector to face.
If you want to know how I did this in more detail, I’ve already written it up for you! Photography and Photoshop How To