Film Noir Styles. Ollie Brocklehurst. Basic Film Noir.
Film noir films were marked visually by expressionistic lighting, deep-focus or depth of field camera work, disorienting visual schemes, jarring editing or juxtaposition of elements, ominous shadows, skewed camera angles, and unbalanced or moody compositions (typically done by the clever use of back lighting).
Here is a tutorial on HOW to light a film noir: