She says...

Ask any child of the '60s and they should be able to remember The Black Beauty, the rolling arsenal of 1966 crime fighter The Green Hornet.

The car had front and rear facing rocket banks, smoke cannons, rotating headlights - four green and two white - and rotating license plates. It had a closed-circuit TV system, front and rear cellphones (a really big deal in the '60s), brooms that swept up its tyre tracks and a whole host of other crime fighting gadgets. Any lover of the comic hero genre will also be familiar with the Batmobile, a sleek stealth bomber of a car capable of amphibious morphings and an able adversary to any joker jalopy or riddler ride.

Collide the two of these comic book cars and you'd get something approaching the BMW Z4 sDrive35i. In fact, if Batman had to take his wheels in for a service, he'd look perfectly acceptable behind the steering of this black diamond of a car. It has the looks, the performance and the style suitable to any super hero.

Our test vehicle is midnight black, shiny and a real eye magnet. It is long, with a particularly lengthy bonnet, and sleek lines that suggest the form of a panther about to pounce. Although other reviewers have found the dimensions of the car's exterior to be too exaggerated, even going so far as to call it "low slung and phallic looking, a look favoured by pre-pubescent boys", I found the Batmobile-esque look appealing because it so powerfully suggests the forward, high-speed thrust that the engine promises to deliver. It's a car that aches to go full-throttle on any road, though it might do itself some damage since it's too low to consider any surface not suitably covered in tar. It's a sexy car in a masculine way, different to the Z3, which was really a lady's car.

Inside, the car's simple design is elegant and more spacious than in previous models. The BMW Z4 sDrive35i packs all the gadgets you'll need, provided you're not saving Gotham City from psychotic make-up abusing malevolents and you don't need rocket launchers or submarine capabilities. It has a premium audio system, iPod integration, and a top-class navigation system. The seats are racing-car-low but comfortable and surprisingly easy to slink into and out of, and the low-slung chassis and laid-back seating position helps you feel at one with the road, though you do feel the bumps and grinds that our pot-holed streets and deteriorating surfaces put us through.

On the road, the car is a bit more of a rough ride than I expected. The seductive growl of the engine provides an ample soundtrack to the sexy drive, but it is also a preview of the coarse ride that is to follow. The seven-speed, double clutch transmission is precise and gear changes are seamless, but the solid build of the car translates into quite a heavy machine to manoeuvre on the road. It's a more substantial car than ever before and you need a heavier foot to drive it.

Thankfully, the engine is beefier to suit the longer, wider, heavier car and the wheel-mounted, ambidextrous paddles put driving the seven speeds of the automatic gearbox at your fingertips. This car goes fast and sticks impressively to the road, but it's body dimensions are too long to execute doughnuts with anything resembling style. (A feat I didn't actually try, but intuited.)

The BMW Z4 is a slicker car than the Boxster or the Mercedes SLK. It has the racy looks of a modern roadster without being as conspicuous as, say, the Batmobile. Knock the centre console switch into sport mode though, and you get the kind of performance and asperous ride you'd expect from the Batmobile.

The BMW Z4 is the kind of car I'd like to have a wild affair with. I'd be assistant DA Rachel Dawes to it's Bruce Wayne. It's the kind of car that can get you in and out of trouble. It races my motor, starts my engine and is a good car to have on your arm, so to speak, if you want to make an impressive entrance. But when all is said and done, the BMW just doesn't have what it takes to turn an infatuation into a lasting relationship. It's immense fun as a toyboy, but just doesn't crack it as a family man.