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The Belles of St. Trinian's is a 1954 British comedy film directed by Frank Launder and starring Alastair Sim, George Cole and Joyce Grenfell. It was the first of a series of films based on the St. Trinian's School for Girls stories by Frank Richards. The film was shot while Moore was still attending Bow Technical College. She played the role of a schoolgirl named Ginger Rogers.