There was only one Countess on each side. My problem is with the word "the". It seems to me that it should be "a".
Interested in Language
from the script to 'Roman Holiday'As she [Princess Ann] sits back into the chair with the Ambassador and the Countess on either side her dress pulls back, revealing the shoe.
There are two Countesses there, as you would see in the movie, and from this quote ("on either side") and both Countesses sit down into the chairs simultaneously.
Why is the singular of 'Countess' used?
not a teacher
As she [Princess Ann] sits back into the chair with the Ambassador and the Countess on either side, her dress pulls back, revealing the shoe.
This is a little confusing. When I first read this sentence I assumed there was an Ambassador and a single Countess, and that they sat on either side of the Princess. Indeed, the script for Roman Holiday at this website only mentions the Ambassador, a single Countess (Countess Vereberg), a General and "others".
Yet you say that there are two Countesses in the scene. Perhaps the film was not shot strictly according to the script in this case.