Setting as character

I've been thinking about setting, this week. In Romance, setting is vital. Mills and Boon talk about setting in their guidelines for the various lines. The Modern Heat guidelines, for example state the books should be set within a chic, glamorous, and usually urban setting. And the Modern guidelines state that: Readers are whisked away to exclusive jet-set locations to experience smouldering intensity and red-hot desire.
Other lines are not quite as specific, but it is worth noting if writing either a Modern or a Modern Heat that this is what the editors are looking for. The location is just as much part of the story as the characters, and they state that clearly.
But what I'm writing about today is using setting as character. Once you have your ideal location picked, each scene can reveal something new, something that brings the story to life. Breathe atmosphere into the scene, and use the setting to reveal something new, that the story hasn't touched on.
Okay, an example. Sherlock Holmes. The wonderfully atmospheric backdrop of foggy London brings a darkness, a lurking menace. As does Hogwarts in Harry Potter, the weather is often stormy and the sky dark, especially in the scenes where the characters are in trouble. It foreshadows the drama to come. Also in scenes the setting can be used to great dramatic effect when it contrasts with the action. Think of a beautiful summer day, and the shock of a dead body suddenly come upon. Or a heroine in love, in the bright sunshine of a garden, and the effect suddenly coming across her lover with another might wreak.
Hmm. Back to writing!