Once strictly the domain of historic houses and celebrity panic rooms, creating a covert space has gone from an eccentric whim to a must-have feature.

Discover these hidden hideouts from reading nooks tucked into wardrobes to a safe room lurking behind a fireplace – and much more.

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

Incredibly, the full wall column with its black marble fireplace is furnished with a fully automated opening and closing system. It slides smoothly aside – fireplace included – to reveal a secret passageway and additional rooms beyond.

That's what we call a big reveal!

While about 20% of Creative Home Engineering's clients order hidden rooms for a sense of fun, the remaining 80% do so due to security needs – but who says secure rooms can't be glam?

This luxurious bathroom is the last place you might expect to find a concealed door, but it turns out it's hiding a little secret...

Yup, that ornate mirror covered in real gold leaf isn't just handy for checking your outfit or perfecting your hair – it swings open to reveal a hidden space behind it. 

Operated by a secret switch, the door is kitted out with an electromagnetic locking system and auto-open feature.

"I think people that order hidden rooms for fun, love it because they are so prevalent in the movies and in pop culture," Steve Humble of Creative Home Engineering says. "But the security side is really where the appeal lies because secret doors can provide much more protection than a safe or vault door."

This motor racing fan called on the company to create a concealed safe room – and they didn't disappoint. Can you guess how you might get in?

If you guessed that this display case slides apart to reveal a secret door you should definitely consider a career as a spy.

The high-quality bookcase is made from painted alder wood, while the heavy-duty door is equipped with an electromagnetic locking system with fully automated opening and closing.

When DeForest Architects designed this house in the high desert of Bend, Oregon they created the 'Swiss Army knife' of homes, with multiple sliding and swinging panels moving to create flexible, tailormade spaces that expand and contract depending on the changing needs of the owners.

This wood-clad wall, for example, is much more than it seems...

The wall section is actually hinged, so it can be closed to turn a sunny sitting area into a guest bedroom.

We love how the secret door can be pushed right back to integrate with the wall, turning a secret passageway into an open corridor.

We'd love to kick back and relax in this super-slick media space – but who would have guessed it's hiding a secret space within it?

Does the TV slide aside or a trap door open in the floor? Let's take a look...

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No! A panel in the concrete wall swings open to reveal a safe room hiding within the open-plan living area. 

Did you detect the camouflaged space hiding in plain sight?

This billiards room might look like a regular – albeit very cool – retreat for sports fans, but somewhere in this space there's a hidden entrance to a top-secret hidey-hole. Can you spot it?

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

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

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.

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 a useful overflow space.

Upon first glance, you'd be forgiven for thinking this wooden staircase was just like any other. However, it was designed and made by the secret spaces experts at 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 that looks totally invisible to the untrained eye.

This slate surface looks like a regular clad feature wall, but give the stone door 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, an Arizona couple 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 stained cherry wood fireplace opens to reveal a safe space, which the pair can retreat to in the event of a home invasion. 

The contraption features a heavy-duty steel door backer and dual hidden 1200lb (544kg) electromagnetic locking system. The hidden space cost a total of $15,000 (£11.3k) – money well spent in the client's opinion.

Hidden on the top floor of a fairytale castle in Banner Elk, North Carolina there's a disguised sleeping space for those who desire a bit more privacy. This playful Airbnb sleeps 20 people, so a secret hideout could be just the thing. 

According to the listing: "The Hidden Castle invites you to uncover secret rooms, explore winding passageways... and wander the grounds, enveloped by forty years of moss-covered stacked stone walls."

At the top of the stairs, the bookcase swings on a hinge to reveal the space inside.

"On the top floor, guests will find two bunk rooms, each sleeping four guests over four twin beds. The second bunk room can be found hiding behind a hidden door that masquerades as a bookcase."

With small but comfortable beds, this room would be an unforgettable place for children to stay on a family holiday!

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