Lighting is one of the most important aspects of a dramatic room. The key to making dramatic lighting is having a clear focal points. Try a chandelier over a dining table or shaded lamps in the bedroom.
Using bold unique colors create a dramatic feel in the room along with contrast. Working with two contrasting colors adds the most depth in a room.
Shine and reflection
Stainless steel, crystal, and marble materials work really well with dramatic lighting. Shine and reflection can add a layer of detail to the room.
You could always use a nice wall covering but if you really want to have a serious feel to the room use texture in a more natural subtle way. Adding marble or a mohair to a room can set it apart and they fit most styles.