What's the big deal? It's the first Mondrian property outside the United States, the first hotel with head-to-toe interiors by British design supremo Tom Dixon and, at 359 rooms, it ain't small. Located in a 1970s office block formerly called the Sea Containers Building, after a previous tenant, it brings fun, frolics and cocktails to a hitherto forlorn and faceless section of London's South Bank. Tell me about the design. It's not subtle but, for the most part, it works (the giant electric-blue chain sculpture in the lobby being an exception). From the long theatrical ramp at the entrance and hand-beaten copper "hull" that sweeps through the lobby and into the restaurant to the artsy yellow submarine suspended above the bar, the design is distinctly nautical and inspired by the Thames, which glistens outside. The building's original architect, Warren Platner, designed ferry interiors for the Stena Sealink line and created the ocean-liner interior of the Windows on the World restaurant at the top of the doomed World Trade Centre, in New York. Accordingly, the communal spaces, including the gorgeous ground-floor toilets and art-deco rooftop bar (but excluding the wonderfully wacky lifts; below) have the look, feel and brass finishes of the great transatlantic liners of the 30s (a five-metre-long model of the Queen Mary in the lobby pays tribute to the glamour of that era). Are the rooms nautical, too? Yes, but not so much so that you feel as though you're drowning in the theme. Porthole-reminiscent curved mirrors and the compact built-in furniture of a high-end ship cabin set the scene. Not being able to see the Thames Path below, guests in river-view rooms could feasibly imagine themselves perched on the deck of a ship. Nice touches include wooden floors, lamps with chunky dimmer switches and shocking pink-lined mini-bar and wardrobe (intended as a cheeky take on a Savile Row suit). The pink-grey-and-black colour scheme and Dixon-designed drip-paint vinyl artwork in each room might leave guests cold but the heady views of St Paul's and other London landmarks should compensate. What about the food? As well as a brash yellow-brown-and-purple colour scheme, open kitchen and wood-fired grill, the restaurant boasts a big name in its culinary director - New York chef Seamus Mullen (but not in the kitchen, apparently). The menu is on the short side and offers yet another variant on the ever-popular sharing concept; dishes come - rather tiresomely - as and when they are ready. The roasted Mediterranean sea bass with citrus salsa verde is delicious but insubstantial; the tuna crudo and gem lettuce salad with soft-boiled egg, croutons and anchovy vinaigrette (that is bafflingly short on egg) are competent but unexciting. Bread and butter/olive oil isn't an option and the experience is accompanied by distractingly loud pop music (Mondrian policy, says our affable waiter). Having sampled pre-dinner "seasonal" cocktails - some of the best we've had - in the green-pink-and-brass Dandelyan bar (above) next door, the disappointment is all the greater. What else should we know? The Agua Bathhouse & Spa (above) is located below the water level and boasts a geometric-patterned steam room and Glamour lounge for communal mani/pedi/make-up parties. The range of treatments and brands is eclectic, exciting and mostly organic. Oh, and there's a 56-seat screening room that functions as an art-house cinema on weekends. The rooftop bar - the rather oddly titled Rumpus Room - is mystifying. Nightclub-style security, a drop-dead dressy crowd and music so loud it makes your brain rattle could be a turn-off to some. What's the damage? Standard rooms (below) start at £195 (HK$2,370), excluding tax. River-view rooms start at £305.