Screen tests can be interesting just on their own merits, especially when they show us a future superstar before they're famous.  Other times, though, especially when they're generally perfunctory formalities for big stars who are generally assured of getting the part, they serve as what we now think of as DVD bonus material fodder: chances for the actors to let their hair down and chat with directors or producers in a format not unlike a talk show.

Roman Holiday, in 1953, was the movie that made Audrey Hepburn a huge international film star, and it was her screen test that caused William Wyler to cast her in the romantic comedy.  The camera was left running after she finished her audition, and she began candidly speaking about her childhood — including, as seen here, her experience dancing at secret performances to raise money for the Dutch underground during the Second World War.  Look at the expression of wicked, playful joy on her face when she describes why the Germans didn't shut them down, and you'll know why so many people were charmed by her in the film.