Bangle reveals first the wheels of the car, then its flanks, and on up to the hood, all the while acting as a kind of master of ceremonies in overdrive: "We call this 'flame design' . . . the splines hold the tension . . . these are surfaces that move; it's 'ooh, here we go' . . . proportion, surface, and detail all convey emotion, and yet they are all under control . . . control, control, control -- it's the most important thing." But then he stops. It turns out that this is a bit of a strip but more of a tease, for Bangle resists baring the entire car, BMW's 2003 Z4 sports convertible. There will be no full-frontal display of the Z4 before it makes its official debut at the Paris auto show in late September. At the push of a button, the Z4 takes a slow turn on a revolving platform. "This is it!" Bangle exclaims. "An absolutely hyper-modern roadster, full of mega-emotion."