What's the news?

It's the fully expected soft-top version of BMW's latest 8 Series, bearing the rather obvious title of 8 Series Convertible. Market launch for this grandest of open-top BMW driving experiences should occur in March 2019.

Any big changes to the mechanicals?

Not really. The 8 Series Convertible will kick off with the 840d and M850i drivetrains as seen in the Coupe, both of these hooked up to the eight-speed Steptronic automatic gearbox and xDrive all-wheel drive.

An automatic, four-wheel-drive, luxury convertible? Light, much?

Well, no, not really, and that's despite BMW using a lot in the way of aluminium, magnesium and carbon fibre in the Eight's make-up. However, Convertible-specific underbody bracing lobs mass back into the equation, so you're looking at a BMW that weighs either 2,030kg as the 840d or 2,090kg as the M850i.

Oof. So they're not quick?

Where would you get that idea from?! The 3.0-litre, six-cylinder 840d gets 320hp and 680Nm, while the 4.4-litre, V8 M850i has whopping outputs of 530hp and 750Nm to play with. So, while both Eight Convertibles are limited to the pesky 155mph maximum speed of most big German machines, the 840d will hit 62mph from rest in just 5.2 seconds. The M850i, meanwhile, has monstrous pace, with a 3.9-second 0-62mph sprint possible. And, just in case you're wondering, yes, there's already a full-fat M8 Convertible in the pipeline.

But I bet they're not great on fuel?

BMW, as one of the first manufacturers to get all its cars homologated through WLTP, quotes NEDC-correlated numbers of 47.9mpg with 155g/km CO₂ for the 840d xDrive Convertible, with 28.5mpg and 225g/km CO₂ for the M850i. Both respectable sets of data, given the prowess and performance on offer.

Can we have a look at the aesthetics and interior?

Sure can, although - apart from the roof - it's all 'as you were' from the 8 Series Coupe on the visuals front. That means colossal kidney grilles, slim front light clusters, strong horizontal lines in the rear and a cabin dominated by the new BMW dashboard, which is generally a Very Lovely Thing. Mind you, we found the rear seats to be a little, er... intimate in the Eight Coupe, so the need to stash the folding roof behind the passenger compartment is probably going to seriously limit the credibility of BMW's claims to this being a full four-seat drophead. Nevertheless, the fabric roof promises quiet operation and excellent acoustic/thermal properties, while it can be raised or lowered in just 15 seconds. This is possible on the move at speeds of up to 31mph, too. Black or Anthracite Silver are your colour options for the fabric, by the way. Oh, and the rear seats have a 50:50 split through-loading facility, while the boot space is 350 litres, in an attempt to salvage some of the Eight's practicality.

Any equipment to speak of?

A full range of kit will be either standard-fit or optional on the 8 Series Convertible, such as a wind deflector, neck warmers in the front head restraints, Sun Reflective Technology leather upholstery, Adaptive M suspension, Integral Active Steering, mixed-size tyres on 20-inch alloys, an electronically locking M Sport differential, the Driving Experience Control mode switch with the Adaptive setting, active roll stabilisation (available on the M850i only), various exterior and interior styling packs and the full gamut of Adaptive LED and BMW Laserlight with Selective Beam illumination options. Expect the Convertible's pricing to command a significant premium, over and above the £76,270 starting point of the 8 Series Coupe models.