Bookcases, fireplaces, cupboards and walls aren't always what they seem, as these weird and wonderful homes prove. Discover a secret retreat hidden inside a wardrobe, stairs that turn into a trapdoor and a safe room lurking behind a fireplace – and more.

Click or scroll on to take a sneaky peek inside some of the world's most clandestine cupboards and stealthy spaces...

Based in Gilbert, Arizona, Creative Home Engineering specialises in designing, crafting and installing secret doors and spaces in people's homes. 

Whether panic rooms or just clandestine hideouts for adults or kids, their creations are some of the coolest we've seen – and this billiard room retreat is no different. Can you spot the entrance to the hidden room?

That's right, the corner shelving unit inside the plush games room is actually a secure door, which leads to a secret safe room.

Should any unwanted persons enter the home, the bookcase door is finished in cherry wood and features an electromagnetic locking system for maximum security.

The owners of this impressive property, an active family of five, had been coming to a rental cabin on Lake Wenatchee, Washington, for years and were ready to build one of their own. They hired DeForest Architects to create them a house that "unfolded in time and space, rather than giving away its secrets all at once," lead architect John DeForest said of the project.

Can you spot one of the home's hidden secrets?

Disguised as a set of open shelves, placed between a built-in seating nook and the staircase, a hidden door opens to reveal a media room.

Since the owners wanted to create flexible spaces that could accommodate their kids and guests, but also didn’t feel too large when it was just the two of them, the concealed media room acts as useful, and very cool, overflow space.

How's this for a clever closet transformation? A teen-friendly take on the secret wardrobe room, this cosy hangout was created by interior designer, Laura Medicus, for her daughter Sylvia by simply walling off the existing walk-in wardrobe and cutting off the back of an old armoire to make the 'door'

Needless to say, the super-snug secret room has become Sylvia's go-to destination for kicking back, reading and gossiping with her friends, as well as watching her favourite shows and surfing the internet on her iPad.

Upon first glance, you'd be forgiven for thinking this wooden staircase was just like any other. However, it was actually designed and made by secret spaces experts, Creative Home Engineering.

Perfectly mundane and ordinary looking, these stairs are far more than first meets the eye...

Amazingly, the staircase sits on top of a highly secure and fully motorised trapdoor, which can be lifted up at the touch of a button to reveal a hidden understairs hangout.

Formed from hardwood over a core of aluminium, the stair door is impenetrable, so the space can be used as a secure hideaway, in case anyone uninvited enters the home. How's that for genius?

This custom clapboard home in Belmont, Massachusetts, is notable for being one of the greenest residential properties in the state.

The handiwork of Platt Builders, the house has everything from low-E windows and high-performance insulation to solar panels on the roof.

If the home's virtuous green credentials don't impress, this hidden mini passageway surely will – the tiny space links two of the children's bedrooms and makes for an unexpected addition that no doubt provides hours of fun.

Here's another fantastic hidden room by Arizona-headquartered company, Creative Home Engineering.

This slate wall looks like it has nothing to hide, but give the surface a little push and you'll find yourself inside a secret space. 

Akin to a louche speakeasy from the days of prohibition, the lounge is elegant and undercover, with timber walls and everything you could need to unwind. Shut the door and you'd never know the room was there!

Just imagine discovering this in your home, it really is the ideal hideout!

Concerned about their personal security following a series of burglaries in the local area, Arizona couple Scott and Maria Jensen hired Creative Home Engineering to design and build a safe room they could escape to if the unthinkable were to happen.

A secret switch on the mantelpiece of the couple's fireplace opens to reveal a safe space, which the pair can retreat to in the event of a home invasion.

Money well-spent in Mr and Mrs Jensen's opinion, the hidden space cost a total of $15,000 (£11.3k).

Loved this? Now discover more unusual homes around the world