Homes with hidden rooms and passageways

Photo courtesy of Zillow

Bookcases, stone walls and wooden floorboards aren't always what they seem. Sometimes, they contain secrets.

All over the world, homeowners with a sense of humor (or a fine-tuned appreciation for spy movies) are working with designers and contractors to create secret spaces, invisible to the naked eye. Most require people to know about a hidden lever or a special code to get inside: Think the candlestick scene in "Young Frankenstein" or the passage to the Addams Family vault, controlled by pulling a secret book.

Some secret areas in homes feature pretty advanced technology, like a hidden home movie theater with a door that seamlessly blends into the surrounding stone walls and is opened by pushing three stones in sequence. Others are simpler: In one Los Angeles abode, adding two tiny doors to a hollowed-out area under the stairs transformed the otherwise useless square footage into a picture-perfect playroom.

Some hidden nooks and crannies are new, like a sleek, spiral-shaped wine cellar located under a trap door in one London kitchen that can hold up to 1,450 bottles. Others are features of very old buildings that were recently preserved. One 19th century home (which used to be a mill) in New York's Catskill Mountains features a trap door in the living area, complete with an old-timey pulley system to help it open and close.

Here are 10 homes with quirky secret features that are worth a second look.

Secret wine cellar – Seattle

Photo courtesy of Creative Home Engineering

This secret wine cellar in Seattle is part storage solution and part spy accessory. The homeowner is a wine lover whose hobby has a personal twist: The custom wine bottles (pictured here) are named after the three children who live in the home, according to design firm Creative Home Engineering. When the bottles are turned in a certain sequence, the hidden stone cellar door opens. According to the company, those aren't the only notable bottles in the homeowner's collection. The hidden room also contains many other "very special/expensive wines."

Secret basement room – Columbus, Ohio

Photo by John Evans of JE Evans Photography, courtesy of The Cleary Company

This Columbus, Ohio, basement was fully renovated in 2013 and now features a hidden storage area that makes the finished area a more polished space for entertaining. The wooden shelving comprising the secret door to the room sits behind a wine bar and kitchenette. As with any good hidden room -- and especially because the homeowners are hardcore James Bond fans, according to design firm The Cleary Company -- the door is opened by pulling a lever that looks like a book on the shelf. When the homeowners' nephews saw the secret area, they quickly identified it as a good spot for sleepovers, according to the designers.

Secret wine cellar – Tacoma, Washington

Photo courtesy of Zillow

This four-bedroom, four-bathroom home in the North End neighborhood of Tacoma, Washington, has a secret: Adjacent to its 400-square-foot lower-level living area is a hidden wine cellar, covered by a thick wooden door, covered by two fully functioning bookcases. Inside the cellar are wooden wine racks providing ample storage for well over 100 bottles. The teal-colored space also features industrial gallery lighting. Outside, a carpeted sitting room features a brick fireplace with more built-in shelving.

Secret home theater – Toronto

Photo courtesy of Creative Home Engineering

In Toronto, Creative Home Engineering (a company specializing in secret rooms and passageways) designed this hidden home theater, covered by a stone wall and casually placed decorative green vase that functions as a decoy. This entertainment space requires a three-part push code to get inside: The owners push three stones in a specific sequence to open the stone-covered wooden door. Inside, the room features tiled flooring, wooden wall paneling and gallery lighting.

Secret stairwell – Genova City, Wisconsin

Photo courtesy ofA. Perry Homes

This white, wooden, shallow bookshelf door in Genova City, Wisconsin, hides a stairwell leading to a secret poker room on the home's upper level. The books were cut in half and glued in place, creating a façade that's truly deceptive but not entirely functional. The secret door opens by pulling a small version of Rodin's "The Thinker" sculpture, which is actually a handle.

According to A. Perry Homes president Anthony Perry, the hidden area includes a separate powder room, wet bar and snack area. It also features a small dome called a cupola that looks like a lighthouse from the outside. "[The owner] wanted a space to hang out with the guys that would be private," Perry said. "When that light is on, it signals to friends in the neighborhood to come on over. When it's off, it means there's no party going on right now."

Spiral wine cellar – London

Photo courtesy of Spiral Cellars

This wine-lover's kitchen transformation in London included the addition of a wine cellar below the floor and covered by a secret wooden trap door. According to the West Sussex-based company Spiral Cellars, which specializes in high-end, spiral-shaped wine cellars built below the floor, this miniature wine room is about 8 feet deep and can store up to 1,450 bottles. Wine storage in this style costs around $40,000 to install.

Secret hideout – Los Angeles

Photo courtesy of Von Fitz Design

The three young boys who live in this home on the west side of Los Angeles consider the secret room under the stairs their favorite spot, according to designers Maria Von Hartz and Annie Fitzgerald. The contractor originally planned on sealing up the space, but instead two hidden doors were added -- one under the stairwell and one inside a coat closet -- and hardwood flooring was installed inside. The room was painted green and is a cozy space for toys and cushion seating.

Hidden door – Penobscot Bay, Maine

Photo by Jonathan Wallen, courtesy of Peter Pennoyer Architects

The owner of this home on the coast of Maine has a taste for the uncanny, according to Peter Pennoyer Architects. After installing this teal-colored secret bookcase door in the library, the contractor heard a creaking sound and almost put some oil on the wheel that allows the door to open.

"We were able to stop the contractor from oiling the wheel as the client actually liked this somewhat spooky squeaking sound," the architecture firm said in a statement.

The hidden door with concealed hinges leads to a room with a small bar.

Living room trap door – Jefferson, New York

Photo courtesy of Zillow

This property in the Catskill Mountains of New York was first constructed in 1856 to be a grist mill (grist is a type of grain). In 2011, it was purchased by a "prolific upstate artist," according to Curbed, who turned it into a home and studio space. Currently on the market for $575,000, the home has many of the mill's original features, including a wooden trap door in the living room floor -- opened and held up by a pulley system -- that leads to a cellar area.

Secret entertainment room – Dallas

Photo courtesy of Creative Home Engineering

Behind a cherrywood bookcase in a red, brightly lit football-themed billiards room in Dallas sits a secret extra space for entertaining. Owned by an NFL player (though his identity, like the room, is a secret), according to Creative Home Engineering, the "exotic" hidden area can be accessed in one of two ways: Prospective guests either have to twist one of the trophies on the shelf or pull on a special book-shaped lever.