'Elementary' Set Tour With Lucy Liu: Sherlock's Brownstone Is Bigger Than It Appears [Exclusive Video]

"Heroine" - Sherlock and Joan (Lucy Liu) once again find themselves in the crosshairs of the enigmatic Moriarty, on the two-hour season finale of "Elementary."

Did Lucy Liu just wake up in her trailer and decide to give a tour of the "Elementary" set with bed head? It sure looks like it in this exclusive behind-the-scenes peek from the "Elementary — The First Season" DVD collection, in which Liu gives the audience a tour of the studio where scenes in Sherlock Holmes's brownstone apartment are filmed. Sometimes, dressing up for bed is just part of the job, and it's not always glamorous — even if she still looks gorgeous!

Liu, donning a large T-shirt, explains that she did not just wake up and decide to give a tour. She is actually prepared for the next scene, in which Liu (as Dr. Watson) wakes up with "bed head," as she puts it, shocked to see Sherlock (Jonny Lee Miller) having a moment of reflection while staring at her sleeping.

[Related: 'Elementary' Casts Rhys Ifans as Sherlock Holmes's Brother in Season 2]

What's particularly surprising about the set? The size of the studio where the cozy brownstone scenes are shot! The studio is enormous, open, and airy. The brownstone is small, dark, and dingy. How do they make something bright and open appear to be dark and small? With lighting, of course.

Liu spends much of the clip showing how the various scenes are lit, from workers setting up the lighting high up in the rafters to director of photography Ron Fortunato figuring out how to light a space within the apartment.

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This sneak peek is from the "Set Tour With Lucy Liu" featurette, which will be available on disc six of the "Elementary — The First Season" six-DVD set. The set will also include all-new cast, creator, producer, and crew interviews — as well as a five-part Web series called "Power of Observation." A seventh bonus disc, available exclusively at Target, will include the "Elementary Super-Sized" featurette, which contains the making of the post-Super Bowl episode, "The Deductionist."

The DVD set will be released on Tuesday, 8/27 from CBS Home Entertainment; and Season 2 of "Elementary" will premiere on Thursday, 9/26, at 10 PM on CBS. 

Check out episode photos from "Elementary":