In her first musical role since Mamma Mia!, Seyfried plays the elder incarnation of Cosette, the orphaned daughter of Fantine (Anne Hathaway) who grows up in the care of Jean Valjean (Hugh Jackman).
Speaking to Digital Spy, Seyfried discussed the challenge of singing live on set, the lack of ADR used for the songs, and the work she and co-star Eddie Redmayne had done to expand on their characters' relationship.
"Most of the rehearsal was just Eddie and Tom [Hooper, the director] and myself, just recreating, or trying to actually rewrite some stuff, or maybe add some stuff, to make our storyline make more sense," she explained.
"It comes so quickly in the stage show, and we needed to make this believable, we needed to make it authentic. We spent a lot of time going through the book, and finding ways to colour it in... to make Marius seem less weak, and Cosette seem less of a child."
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Watch Digital Spy speaking to the cast of Les Misérables at the world premiere below:
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