After a week of teasing, Mercedes-Maybach has at last revealed the Vision 6 concept coupé, just ahead of this weekend's festival of vehicular excess, the Pebble Beach Concours d'Elegance in California. The car seats two — only two — in futuristic comfort, and moves down the road not with a roar, but a hum. The powertrain bears a striking resemblance to that of the limited-production Mercedes-Benz SLS AMG Electric Drive, with a quartet of synchronous electric motors, fed by a bank of lithium-ion batteries, producing a healthy 738 horsepower. The company promises the car will lope from zero to 62mph in less than four seconds, reach a (governed) top speed of 155mph and cruise for 200 miles between charging stops.

Like a bad online dating profile, the car announces its size right up front: The Vision 6 stretches, yes, 6 metres from bumper to bumper. That's about a Montecristo cigar short of 20 feet — longer than a Rolls-Royce Phantom Extended Wheelbase saloon. Such a measurement may seem outlandish, even obscene, for a two-door, two seat automobile, but really, it takes no more than a cursory glance at Maybach history to realise that, ahem, size runs in the family; everything from the company’s heyday, in the 1920s and '30s, was cartoonishly outsized. And even the Vision 6's size-name has a precedent: When parent Daimler revived the Maybach marque in 2002 after a 60-year hiatus, it named the two production models, the 57 and 62 saloons, for their respective lengths, 5.7 and 6.2 metres. In Maybachland, size matters.

And though the Maybach name is hardly synonymous with gargantuan coupés, this is not the marque’s first attempt at this most imposing of automotive forms. In 2004, Maybach created the monstrous Exelero concept coupé (pictured below), a 19-foot-long supervillain express with 700 horsepower and a rakish shape purportedly inspired by Maybach's similarly rangy SW 38 Stromlinie (Streamliner) test car of 1939. Only one was built.

No surprise, the Vision 6 is awash in glam-tech, including and a common-sense-be-damned augmented reality projection system that displays vehicle and navigation information across the full width of the windscreen. The seats feature dozens of button-like sensors which, in addition to monitoring the sittee's vital stats, "also record the incidence of light, the colour of the occupant's clothing and the ambient temperature", with the goal of fine-tuning ambient mood lighting to match your ensemble.

The Vision 6 concept may have a better shot at reaching the production line than the Exelero, though if it does, it will likely define a class of one. The Rolls-Royce Wraith and Bentley Continental GT are petrol-guzzlers, and neither can't match the Maybach's expansiveness, and the very grand Rolls-Royce Phantom Coupé is about to reach the end of its road. The Vision 6 perhaps most closely resembles — in its degree of its splendour if not in its form — the recent Rolls-Royce 103EX autonomous concept, although unlike the Rolls' pampered occupants, the Maybach's driver is expected to actually drive. One thing about the Mercedes-Maybach Vision 6 is certain: It will roll into territory not occupied since Lady Penelope bedazzled London in the FAB1.

This story, originally published on 12 Aug, was updated with new information on 19 Aug.

Care to share your thoughts on this mighty Maybach? Head over to our Facebook page or message us on Twitter.

And if you liked this story, sign up for the weekly bbc.com features newsletter, called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Autos, Future, Earth, Culture, Capital and Travel, delivered to your inbox every Friday.