Monday Mystery a non-Voisin Boattail

I don't think I have ever seen a picture of a coupe with only one door. Do they exist? And I mean something built by a notable company, not an eccentric one off.

This is a very nice looking body but the photo is not very clear. It could have been retouched but I don't think so. As it is a fabric covered body which has an embossed pattern on it this acts to diffuse the glare of the sun, so it is over a wider area. The main area of glare on this body is where the door handle is situated and I think this is why you don't see it. I can make out the shut lines which are faint and show as a light glare on the door frame. I also see similar ribs on the back of both fenders. Could the wheels and hubs have been upgraded? Yes.

The car could well be a type 23 Bugatti. These very often had the RAF hubs, and the wheelbase seems right (2,55m). They also had the gear lever and hand brake on the right side, which would explain the absence of a door, which would be useless. I agree that the bonnet probably is not completely closed

The shape of the radiator suggests somehow BNC,same for the wheels

Although my initial reaction was also Bugatti, upon closer inspection I say: probably not. On a Bugatti (type 40? 44?) you would see more of the brake drums through the spokes. Also Bugatti didn't use these type of wheel nuts. So what is it??
Do I see it correctly that the front mud guards don't have the subtle profile ('fin') that is visible on the rear ones? That would make this body more put together from existing parts than designed as a whole.

I would suggest that perhaps the bonnet is not closed correctly, therefore the odd shape.

I agree that not Voisin. The hubs look like RAF 52 which would point to a French make.