British actor Tom Hiddleston spent months learning how to sing like one of country music's most iconic voices, the late Hank Williams, for the new biopic, "I Saw the Light". Luckily, Hiddleston was assisted by singer and songwriter Rodney Crowell.

British actor Tom Hiddleston spent months learning how to sing like one of country music's most iconic voices, the late Hank Williams, for the new biopic, "I Saw the Light". Luckily, Hiddleston was assisted by singer and songwriter Rodney Crowell.

Hiddleston's musical preparation for this role meant being thrown in the deep end.

"His first question was 'Can you yodel?' Which is, there is a time in a man's life when he is asked that question. I had never yodeled before and it is an interesting. You have to do so much. There's so much technically that you have to do with your voice, but it's also about yielding. It's about freedom. You have to let it all happen. You can't force it," said Tom Hiddleston, actor from "I Saw the Light".

Hiddleston wasn't the only actor who had to sing on set: co-star Elizabeth Olsen -- who plays Williams' wife Audrey -- had to learn how to sing badly.

"Our tones, the tones of our singing voices, Audrey and I, are very different. But I can tell when she goes flat and I can tell when her version of a yodel is really just a crack, and trying to capture those sounds that make her singing endearing and play with it with Rodney and Marc, and trying to find a balance of bad enough but not so bad that she would be such in denial and he would look like an idiot," said Elizabeth Olsen, actress from "I Saw the Light".

"I Saw the Light" is a warts-and-all exploration of Williams' life, which was blighted by alcohol and drug abuse.

"I don't know what people sometimes go to movies to expect and they expect to see a certain guy. This is actually a movie about the trials and tribulations and the difficulties and complications of the things that go on behind the scenes and how those things are the impetus for the great poetry that this man happened to write," said Marc Abraham, director of "I Saw the Light".

"I Saw the Light" is released in the U.K. and Ireland on the 6th of May.