Marion Cotillard found it "very impressive" watching Michael Fassbender juggle producing and acting on 'Assassin's Creed'.

Michael Fassbender

Michael Fassbender

The actress stars in the upcoming videogame adaptation as the mysterious Dr. Sophia Rikkin and says it was easy to see just how passionate her co-star - who plays main protagonist Callum Lynch - was about the film.

She said: "It was really impressive to see him in that different context.

"Michael was full of ideas and creating things with Justin [Kurzel, director] on set."

The movie marks the second collaboration between Michael and the director, having previously worked together on 'Macbeth', and though the actor admits his producer role has impacted on their working relationship, they still have the same "language".

He told Empire magazine: "Basically I just annoy Justin more [now].

"It's just a different beast, you know? We worked on the script together and now, in post, it's a longer journey.

"But the language remains the same, in terms of how he speaks to me."

The 39-year-old star has always been interested in production "from the beginning" of his career.

He explained: "I enjoy it. It's something that has always interested me, from the beginning when I stumbled upon acting through Donie Courtney.

"He was a pupil at my school who went off and studied at the Gaiety School of Acting.

"We had no drama class, so it never occurred to me that was an avenue I could go down until he came back to teach classes.

"I joined a company he set up and then six months after, set up my own prduction company, Peanut Productions.

"We did a play of 'Reservoir Dogs', which I directed, produced, and acted in. So from the beginning I've always been interested in it."