The 27-year-old actress said that being cast as Cosette in director Tom Hooper's musical adaptation gave her the most defining role of her career till date, reported Digital Spy online.
"The moment I auditioned for Tom Hooper, everything changed. He gunned for me. What's most important to him is an actor who can get it and who can be grounded enough to make it believable when she bursts into song," she said.
Seyfried has received wide critical praise for her portrayal of Cosette, earning both Satellite and National Board of Review award nominations.
"Les Miserables" also stars Hugh Jackman, Russell Crowe, Anne Hathaway and is now playing in the US and opens in the UK on January 11.