Wielding the wand is Otto Ng Chun-lun, who turned theory into reality when he and the design studio he co-founded, LAAB (a "laboratory for art and architecture"), transformed a tiny flat into a smart home that accommodates a large TV for movie nights, a generous kitchen, a dining room, space in which to exercise and guests, should they stay over.

That's just for starters. There are items unusual even in apartments twice the size, including a dishwasher, a wine fridge and an oven. In this form of one-room living, however, the wardrobe is by the entrance and other storage is under pneumatic hatches on a raised floor.

"The only things we can't store here are our dive kit, which is at my parents' place; his mountain bike, which stays in Tung Chung, where he rides; and my wedding dress," says Tennant, a lawyer who, like her husband, grew up in Hong Kong.

The couple, who for five years lived a few floors down in an even smaller, 240 sq ft rental apartment, started interviewing potential designers after buying their present unit in 2014, sight unseen. Unable to enter the flat because it was occupied by a tenant, the couple viewed a similarly sized unit beneath it for a sense of what they would be calling home.

"The windows sold us," says Knight. Openings on three sides meant the apartment enjoyed abundant light and cross-breezes. But having few walls to work with made it doubly difficult for LAAB, which took three months to design the flat and a further six months to have it built. To make things trickier, the couple wouldn't compromise on furniture: they wanted regular-sized items and kit that, if stashed, wouldn't require much effort to set up.

"We didn't want a Murphy bed," says Tennant, who had the double bed from their previous home fitted into a corner of the flat. Panels on two sides slide closed to give them privacy when they have company. The other furniture, save for a bookcase and chairs, was custom made: a dressing table is fitted into a swing door and the dining table folds so it can be stashed neatly beneath the TV.

As pampered as the owners are their pets, Dumpling, Tuxedo and Banoffee, whose well-being received special attention from Ng and his colleagues.

But just as the cats had to get used to their new home, so Tennant and Knight took time acclimatising to hi-tech living.

"It's like a logic puzzle," says Tennant, and not without its challenges. Twice a glass cabinet door was crushed because it had not been fully closed before the shelving units above it, controlled electronically, came down. Also, she says, it can be awkward preparing meals if the television wall is out. And it's not always a good idea for her husband to turn on the lights remotely before coming home. "If I'm already home and I'm cooking, the lights change and I know he's coming home so I think, 'I've got to cook faster' … or get the toy boy out the door," she says.

But in the year they've been in the flat, has the tight, albeit smart, living caused problems?

"No," says Knight.

"Not yet," counters Tennant.

And that despite their wish list not being completely fulfilled.

"I wanted a hammock," says Knight, smiling. "But we didn't have the space for that."

Styling: David Roden

Kitchen The kitchen was built by LAAB, using a white artificial stone for the countertop and black-tinted hairline stainless steel for the backsplash. A pop-up Artinox tap is hidden beneath the removable cutting board. Shelving at the top is lowered via an “electrical escalator” for easy access. To the left is another kitchen storage area, behind a glass door. A piece of metal, placed over the induction hob controls, ensures the cats do not accidentally turn on the hobs.

Cat ladder The couple’s moggies climb up the carpeted steps of the cat ladder, and through the opening at the top, to leap onto the cat walk. The door also accommodates a dressing table.

Bedroom Philips Hue Gu10 spotlights (available at Apple stores for US$59.99 each) have been set to morning mode so the light comes on slowly and mimics sunrise.

Toilet The Steinberg wall-mounted tap (HK$7,880) came from Massford (from Depot, 345 Lockhart Road, Wan Chai, tel: 2575 0200), the basin from Toto (HK$5,750; 11/F, 3 Lockhart Road, tel: 2861 3177). The faux-wood Atlas Concorde floor tiles (HK$110 per square foot) came from Pacific Gallery (159 Lockhart Road, tel: 2827 9918).

Bathroom Dumpling sits beside a Bette Starlet1 tub (HK$24,000 from Colourliving, 333 Lockhart Road, tel: 2295 6263). The water rises from a tap on the bottom of the tub, as though fed from a spring. When the shower/bath is used, a waterproof roller blind is pulled down to prevent the sofa in front from getting wet.

TRIED + TESTED

A kitchen drawer pulls out to reveal bowls for the three cats, which eat communally at meal times. The Boen natural oak planks (HK$120 per square foot) came from Equal (22/F, 111 Leighton Road, Causeway Bay, tel: 2881 7066).