Hidden away in a quiet corner of Majorca is a car so secret it must be camouflaged every time it appears in public. It won’t be unveiled to the world until September. I’m not allowed to show you its interior — or even be pictured at its wheel — but I have driven it on and off the road, and when sales finally begin in the autumn, this BMW X1 will break new ground.

The X1 is nothing less than the first of a new class of car — a so-called Sports Activity Vehicle. The rivals selected below are merely the closest approximates on sale at the moment. The X1 is smaller than the Land Rover Freelander and has a more premium feel than the Volkswagen Tiguan. There are, of course, a host of small SUVs around, such as the Toyota RAV4 and even crossovers such as the Nissan Qashqai, but we are used to them being slow and dull. The X1 will be faster and more fun to drive than the lot of them.

BMW sees it as the perfect answer to those who want or need a smaller car, no longer wish to be associated with large SUVs but still desire some of their qualities ­— such as a high driving position, rugged image and four-wheel drive ­— and won’t compromise on quality or performance.

The looks are easy to judge because, despite the camouflage, the car has not been disguised by any fake body panels or any other additions — BMW has just covered up the badges and given it a psychedelic paint job. Beneath that lies a smart, clean shape, better than the ugly and unappealing X3, though lacking any great flair.

The most important thing you need to know about the X1 is that inside its compact shape it has the body and soul of the outstanding 3-series. Three engines will be available at launch: the 177bhp and 204bhp diesels from the 320d and 123d respectively, and a 272bhp

3-litre petrol engine, though BMW predicts sales of this last will be ‘‘minuscule’’. More interesting still, the base

2-litre diesel will be available with both rear-wheel and four-wheel drive, with the majority of sales going to the cheaper, two-wheel-drive variant. All other X1s will be four-wheel drive only, at least until a 2-litre petrol model and a lower-powered diesel are introduced at some stage next year.

The car I drove had the 204bhp diesel and, as with most pure prototypes, was full of cheap plastic and minor mechanical glitches. Yet through this shone a car with a real purpose in life. It rockets down the road, hitting 62mph in 7.3sec on its way to almost 140mph — a different level of performance for a small SUV — yet still returns more than 44mpg. Sure, it’s going to be more expensive, but you’re never going to wonder what you’re paying for.

Show it some corners and instead of rolling around, the X1 attacks with real relish and first-class steering. BMW’s only mistake was to let me take it off- road. Even on a course designed by the car maker itself, it grounded out. Unlike the Freelander, it can never claim to be a true off-roader, so it is just as well most owners will ask little more of it than to park in a muddy field at sports day.

Inside is an environment that will be familiar to drivers of the 3-series. There are the same dials, a closely related dash and identical switchgear. Quite why no shots of the interior were allowed is a mystery, unless BMW was keen for you not to find out it contains absolutely nothing out of the ordinary.

The chief point to note here is that the X1 is by no stretch a family car. There’s good space in the front, and the boot is a decent size and shape, but the legroom in the back is tight enough to start anyone other than small children fidgeting soon after climbing aboard.

There are other faults too: the ride comfort is average at best on smooth roads and rather uncomfortable on poorly surfaced streets, especially if you’re sitting in the back. A sports option will be available from launch, featuring stiffer springs, but this is one box I would definitely leave unticked.