I recently saw a plane that I couldn’t identify. I’ve searched all over the internet without finding it. I’ve even asked an aviation magazine, and after searching, they weren’t able to identify it either. Maybe somebody could help me out?

Clues:

1/ It appeared in the 1953 movie classic "Roman Holiday" with Audrey Hepburn and Gregory Peck.
2/ In the movie, it appears as a commercial airliner or possibly a private plane.
3/ It is the general size, vintage and configuration of a Constellation.
4/ The fuselage has a flat back in profile, but is rounded in cross section
5/ It has a low wing.
6/ It has four propellers.
7/ The tail has two vertical tail fins attached to horizontal stabilizers.
8/ It has a tricycle landing gear (is not a tail dragger).
9/ It has a rear stairway that drops from under its belly like a Boeing 727!
10/ It was a pretty plane, but something must have been pretty wrong with it.

What the heck is it?

Extra credit: Whose livery is on the plane in the movie?

The airliner that you refer to is the only Breda-Zappata BZ308 built. Designed in 1942 built in 1948. Bought by the Italian Airforce in 1949. Powered by 4 x Bristol Centaurus 568 engines. 1750hp each. 55 passengers and 3-4 crew. Range 3105 miles (5000km).

Hope this helps!

PDT