'Les Miz': Samantha Barks, Eddie Redmayne on intense auditions For aspiring actors growing up in Great Britain, "Les Miserables" wasn't just a popular stage musical, it was practically required viewing - particularly for Samantha Barks and Eddie Redmayne. Barks spent much of her youth performing a one-girl version of the show on her karaoke machine while Redmayne became obsessed with the play after first seeing it when he was 7. Barks soon left karaoke behind and went on to join the cast of a West End production of "Les Miz" in 2010. And now, at 22 - having beaten out the likes of Taylor Swift and Scarlett Johansson - the actress makes her film debut in the role of the lovelorn street waif Eponine in the adaptation of the classic Victor Hugo novel from director Tom Hooper ("The Kings Speech"). And she'll star opposite Redmayne, who plays Marius the student revolutionary and object of Eponine's unrequited love. The 30-year-old actor, best known for his role as the star-struck assistant in last year's "My Week With Marilyn," is performing in a film musical for the first time after appearing on Broadway in John Logan's "Red." The casting process for the film, the two say, was grueling. How rigorous were your auditions? Barks: [Producer] Cameron Mackintosh knew me from a TV show I did when I was 17 and from playing the role on the West End. So my name was in the mix but so were so many other people. I was a huge gamble [for them]. I had never done a film before. I had no screen experience. And as all these A-list stars were being announced [as potential Eponines], I had no name for myself. I had done the role, I had experience with the role but I had to really prove I could translate that onto the screen. It was over 15 weeks. Working the material, turning the theatrical performance into a film-worthy screen performance. Redmayne: It was a pretty intense audition because the stakes were so high. The tests were full-on, in costume, hair and make-up. They even built us a mini-barricade. The last audition that I did, it felt like something out of an "X-Factor" audition or "American Idol." You were in this little room with the casting director Nina Gold and Tom with a camera here [he indicates inches from his face] and then a panel with Cameron Mackintosh, the two producers from Working Title and [composer Claude-Michel Schonberg]. I suddenly had so much more respect for the "X-Factor" contestants. And I was sort of a wreck both before and after. Why has this musical taken such a hold on you two? Barks: I was 16 the first time I got to see a show in London and "Les Miz" was the first West End show I saw. It completely blew my mind. It left me with the same feeling I had after watching the film: 'I don't know what to do. Do I sit and cry or do I run around going, "Isn't life amazing?"' It's got that effect on you. It brings you down to such a dark place and then it fills you full of hope. Redmayne: It's interesting that it can turn on its head as much as it does. It can go to such places of tragedy but what is genius about what Claude-Michel and tk did is they can add Sacha [Baron Cohen] and Helena [Bonham Carter] as the comedic moments you need and you can come back to the frontal story and at the end leave with some sense of hope. It was amazing seeing it with that huge audience in New York [at the premiere] and the euphoria of humanity at the end. It's exciting to feel a part of that. How difficult was it to sing live? Barks: Tom said this was the most difficult film he's ever had to cast because of those elements. Obviously, you need actors who can really act these parts and not just blag [or fake] these songs in a recording studio but sing, more than you would be required in a West End musical. In a musical for three hours a day you have to be in your vocal peak. But for this, for 2 1/2 months, sometimes starting at 5 a.m., you have to be at your vocal peak. You have to have actors who can sustain that. Not only just sing it but have that stamina. Redmayne: And the vocal warm-ups were genius. We all arrived mildly terrified but nothing is more grounding than watching Wolverine [Hugh Jackman as Jean Valjean] and Gladiator [Russell Crowe as Javert] walking around going 'la la la la.' Any sort of intimidation went out the window. Were either of you intimidated by your solos? Barks: With the solos there was this build-up. Everything hangs on you. Imagine if you woke at 6 a.m. and you had no voice and you were doing your solo. Redmayne: And we all knew when the big numbers were coming and you'd arrive on set those days and you'd hear rumors around the crew: Did you hear Annie's [Hathaway] "I Dreamed a Dream," it was utterly breathtaking. Or did you hear about Hugh's "Bring Him Home," the crew was all in tears. Sam and my solos were at the end, so after a while it was like, "Enough, enough about hearing how virtuoso all the other solos were." Sam did have it toughest. She had to do all of that in the pouring rain. And tears, if you do 10 takes of crying - the tear ducts are attached to your nostrils and start making your nose pretty nasally. And she is shivering, even during her 30-minute lunch break, it's not like you can take off the corset. So hats off to you. It was an amazing thing to watch. Barks: That's the thing when you cry, and there is a lot of crying. Redmayne: It is called "The Miserables." Barks: When you cry you make all these terrible noises and that starts to happen with your voice. So you've really got to control that because there is a fine line between [that and] yodeling your way through "On My Own." It's all those challenges. You still have to honor the beautiful music that has been written but allow that raw emotion to come through. It was a tricky part in striking that balance.