The McLaren MP4-12C Spider is the new convertible version of the 12C supercar.
Like its 12C Coupe sister, it's built around a carbonfibre 'monocell', and this is so stiff that McLaren hasn't felt the need to strengthen the car's structure to make up for the loss of the fixed roof.
As a result, the 12C Spider weighs just 40kg more than the coupe version, with the extra kilos coming from its retractable hard top and a slightly heavier exhaust system.
The electrically operated roof folds away in around 17 seconds at speeds of up to 19mph, while the rear screen can be lowered independently so that plenty of engine sound can reach the cabin whenever it's required.
The Spider also benefits from the revisions made to the 2013 12C Coupe. These include improved exterior door release buttons, a tweaked semi-auto gearbox that delivers smoother and faster shifts, a new volume control for the engine and a 24bhp hike in power that brings the total up to 616bhp.
What's the 2013 McLaren MP4-12C Spider like to drive?
In most convertibles, including the rival Ferrari 458 Italia Spider, larger bumps send shimmies through the steering wheel when the roof is down. However, the open-top version of the 12C feels every bit as rigid as the Coupe.
This helps you place the 12C Spider with precision, even on poorly surfaced roads, plus the steering is well weighted and turns in sharply, yet still offers impressive straight-line stability.
The rigidity of the structure also helps the suspension do its job properly. The 12C Spider soaks up bumps more efficiently than many luxury saloons, let alone other supercars, but there's hardly any body roll – even when it's in its softest setting.
Switch the handling to Track mode and the car's stability electronics will give you significantly more slip before intervening. Fortunately, when the back-end starts to slide mid-corner, it does so in a progressive way that's easy to control.
According to McLaren, the 12C Spider matches the Coupe's performance figures, which means its twin-turbo 3.8-litre V8 fires it from 0-62mph in just 3.1 seconds (when Pirelli P Zero Corsa tyres are fitted) and on to a top speed of 204mph.
Even at low revs, the engine feels responsive, then the turbos chime in and the car absolutely flies; before you know it, it'll be time for you to select the next gear by pulling on the tactile, steering wheel-mounted shift paddle.
Powerful brakes and a rear airbrake stop the car just as quickly, although the back can squirm a bit during the hardest stops.
One of the main reasons for choosing a convertible supercar over the coupe version is that it allows you to hear the engine better on sunny days. While this is the case in the 12C Spider it actually sounds best when you leave the roof up and then lower the rear screen; in this configuration there's little wind noise and the sounds from the engine flood the cabin.
Put it in its noisiest setting (previously this was linked to the powertrain's Track mode, but it can now be done independently) and the soundtrack is fantastic, as the engine mixes a metallic rasp with induction whoosh, before popping and banging on the overrun.
The 12C Spider can also play the refined cruiser if you turn down the volume of the engine and shut everything, but there's quite a bit of bluster in the cabin when you lower the roof.
What's the 2013 McLaren MP4-12C Spider like inside?
As with the Coupe, the doors open up and out, which brings a sense of drama, but means access could be easier.
However, once inside, you'll find there's generous space for two people, and a huge range of adjustment to help you find a comfortable driving position.
The seats and dashboard are beautifully trimmed, too, while the switchgear is unique to McLaren: unlike some of its rivals, the 12C doesn't borrow bits from more humdrum models.
McLaren has finally got the 12C's Bluetooth and satellite-navigation systems working in time for the Spider's launch, and these are simple enough to operate.
There are still a couple of niggles elsewhere, though; the indicators tend not to self-cancel and the various controls for the electric seats are hard to tell apart.
Visibility isn't as good as it is in the Coupe, because the rear buttresses restrict over-the-shoulder vision, but your all-round view is still much better than it is in most mid-engined supercars.
The 12C Spider can carry more luggage than the Coupe when its roof is up (196 litres rather than 144), because the well that the roof folds into doubles as a rear boot, complete with two bags that are designed to help you make the most of the oddly shaped space.
Should I buy one?
If you can afford to spend almost £200k on a car, absolutely. The 12C Spider might not look as striking as its main rival, the 458 Italia Spider, but it's better to drive, whether you're covering long distances or pushing it to the limit.
In fact, the 12C Spider is so uncompromised that it's hard to see why anyone would buy the Coupe. Yes, it's cheaper, but at this end of the market £19,500 makes very little difference.
Our reviews are based on hard data and thorough testing in the real world.
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