Now that the wraps have come Gordon Murray’s revolutionary T25 city car (we scooped it undergoing road trials today) I thought the great man might not mind if I cold-called at his Guildford design HQ, south-west of London, seeking a few more details.

Reception for the car’s shape and concept has been both strong and positive, many people using the word “funky” for the cute and revolutionary styling. However, what nobody understood - because our hastily-snatched picture failed to explain it - was exactly how the T25’s one-piece door worked. If I asked nicely, would Gordon show me?

See Autocar's exclusive Gordon Murray T25 pictures, including the radical 'door' in operation

The answer was yes. I was smuggled into the workshops (where several other fascinating projects were shrouded by hack-proof dust-covers) and shown, in the flesh, the same T25 prototype our cameraman had seen.

First impressions: it’s tiny, but its stance, height and the clever resolution of its distinctive styling give it an impressive presence. That’s good. The last thing you want is for your tiny car to seem toy-like, and the T25 doesn’t.

The door is a typical example of Murray being brilliantly simple, other examples of which are visible all over the car. A large, rigid assembly comprising the windscreen, the side windows and side panels and much of the roof, all swings forward with BMW-like precision to present a low-sided cockpit into which all three occupants can step into with ease and convenience.