The puzzle car is one of three hybrid gasoline-electric cars built, presumably by General Electric, for Ned Green at a cost of over $1 Million. Mr. Green lost one leg as a child, and couldn't drive a conventional automobile. This project would create a car without a transmission, so he could control it with his one leg.
The puzzle car was based upon a 1929 Stearns-Knight M 6-80 Cabriolet. The later brougham and sedan models were also based on Stearns-Knight automobiles. The propulsion system replaced the transmission and driveshaft with a generator and electric motor. The original Stearns-Knight sleeveless engine drove the generator, which powered the electric motor (connected to the original rear axle).
All 3 vehicles were titled as Rauch & Lang.
The puzzle car was scrapped not long after Mr. Green's death in 1936. The brougham was abandoned in a field, but has been retrieved and is undergoing restoration.
The sedan still exists and is fully operational. As of 2011 it was part of the JWR Automobile Museum collection.
Attached are an image of Mr. Green with his roadster, and a recent image of the sedan.