Isabelle Allen is an English child actress known for her role as the young Cosette in the 2012 film adaptation of Les Misérables. Allen was discovered by Jeremy James Taylor, head of the British National Youth Music Theatre after seeing her in the play The Pied Piper in Eastbourne, East Sussex, her hometown. She made her professional debut in the 2012 film Les Misérables as the younger version of Amanda Seyfried's character Cosette, which earned her the Young Artist Award for Best Supporting Young Actress Age Ten and Under.