Saoirse Ronan reveals how hard Ryan Gosling made her work on ‘How to Catch a Monster’

Soraya Roberts

Ryan Gosling made Saoirse Ronan work harder than usual on his directorial debut, "How to Catch a Monster."

The 19-year-old Irish star was in Toronto on Tuesday attending the premiere of her dystopian flick "How I Live Now," about a city girl sent to live in England in the midst of a war in the near-future. But Ronan took time out to speak to Collider about Gosling's directorial debut.

The film, which the Canadian actor also wrote and produced, is a fantasy about a single mom whose son stumbles upon an underwater world. Ronan plays a character named Rat, and the actress revealed that the cast had to think on their toes much of the time in front of the camera.

"A lot of it was improvised. A lot of it was discovered as we went along," she said. "It was really lovely to do that because the relationships the actors started to establish with each other within the story almost started to change. Everything was kind of a surprise every day; we didn't know what was going to happen."

Ronan acceded that Gosling borrowed the naturalist approach to filmmaking from Derek Cianfrance, with whom he worked on "Blue Valentine" and "The Place Beyond the Pines." It was an approach that meant the teen star had her work cut out for her.

"You do need to do an awful lot more work because you're basically, in a way, helping him write the story," Ronan said, though she added, "He had a very clear understanding of his story that he had written and the heart of it and where he needed to go."

"How to Catch a Monster" will hit theaters sometime in 2014.

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