The 12 Years A Slave actor stars alongside current girlfriend Alicia Vikander in the emotionally poignant romance drama, about a lighthouse keeper and his wife who decide to raise a baby they find in an adrift rowboat near their remote island, after years of unsuccessfully trying for their own.

The film presents a moral dilemma when they discover the tot's real mother years later and it is filled many scenes of showing the actors crying, on the brink of tears or extremely sad and depressed. And the Blue Valentine director admits that there were times when they were trying hard not to cry but the emotional nature of the material made it impossible to hold back the tears.

"I have to say when Michael cries early on in the movie, I thought to myself, ‘yeah, here we go,'" he told reporters at a London press conference in an excited voice. "Eight weeks into it, we would be together for scenes, saying, ‘whatever we do, let’s not cry’, ‘yeah I don’t want to cry anymore’ but it was so ripe with emotion we couldn’t stop crying... We couldn’t help it."

He joked that they spent the whole of the shoot "snotty crying" and he is convinced making his cast and crew live on the remote peninsula in New Zealand, which stood in for western Australia island, for most of the time heightened their emotions too - because they couldn't escape the characters' real environment.

"I thought the isolation would play into it, be an X factor to us in making the movie and I think it was in some ways," Derek adds. "We had nowhere to go; we didn’t have technology to escape to. We didn’t have many distractions out there, we just had each other."

The movie is released in the U.K. on 1 November (16).