There are fast cars. There are very fast cars. And then there are cars that appear to have been designed after someone at AMG asked a perfectly innocent question, ignored every sensible answer and wandered into the workshop with a chainsaw.

Meet the Mercedes-AMG CLE 646 Spezialanfertigung.

It is, technically, a coupé. But calling it a coupé is rather like calling a chainsaw a garden ornament. Underneath that wide, carbon-fibre-clad bodywork lurks a 646bhp 4.0-litre V8 biturbo, driving the rear wheels only.

It produces 850Nm and will propel this thing from rest to 200km/h in 11.4 seconds. Keep your nerve — and find somewhere sufficiently large — and it will continue to 310km/h.

And AMG hasn’t achieved this by simply turning up the boost and sticking a louder exhaust on it.

The engineers have removed roughly 170kg, widened the car, reworked its aerodynamics and fitted a bespoke four-way adjustable coilover suspension developed with KW.

You can independently tune high- and low-speed compression and rebound. In other words, this isn’t suspension designed merely to make the car look angry while parked outside a restaurant. It is designed to attack corners.

Then there are the brakes: enormous 420mm ceramic discs up front, clamped by six-piston calipers and fed by dedicated cooling. The rear gets 360mm ceramic discs. AMG has even gone to considerable lengths to keep temperatures under control when the car is being driven like it has just escaped from a racing driver’s garage.

And the noise? Oh, the noise.

A high-flow titanium exhaust, developed with Akrapovič, gives the V8 an appropriately antisocial soundtrack. The flat-plane crankshaft also makes the engine sharper and more eager to respond.

Yet the most ridiculous number isn’t 646. Or 850. Or 310. It’s 30. That’s how many will be built worldwide. And they’re all gone.

So this isn’t merely a very fast Mercedes. It is AMG taking a perfectly respectable CLE, throwing the rulebook into the nearest bin and asking: What if we made the lunatic version?

Apparently, 30 people already know the answer.