McDonnell XP-67 Bat

On 29th July 1941, McDonnell Aircraft Corporation, formed on 6th July 1939 received a contract of two prototypes for its Model 23 long-range single-seat fighter that was designated XP-67 by the United States Army Air Corps and nicknamed "Bat" or "Moonbat".
It was a very innovative design which attempted to maintain true aerofoil sections throughout the entire fuselage. In fact, the centre fuselage and the rear portion of the engine nacelles were merged to give the fighter its unique appearance.
It was powered by two 1350hp Continental XI-1430 12-cylinder inverted vee engines with General Electric D-23 turbo-superchargers with exhaust thrust augmentation. The cabin was pressurised and it was going to be armed with six 37mm M4 cannons, but they never were installed in the prototype that flew for the first time on 6th January 1944 and trials were continued until 6th September 1944 when it suffered an irreparable fire damage.
That accident and the too innovative of the design, led to the abandonment of the project. It was trully a fighter ahead of its time.

Sources:
1. Salamander Books - The Complete Book of Fighters
2. https://en.wikipedia.org/wiki/McDonnell_XP-67