Jamie Dornan will be ''amazing'' as Christian Grey, according to his 'Fifty Shades of Grey' co-star Jennifer Ehle.

The 43-year-old actress will play the mother of protagonist Anastasia Steele - played by Dakota Johnson - in the movie adaptation of E.L. James' steamy book, and she thinks Dornan, who took the lead role after Charlie Hunnam dropped out of the movie, is a wise replacement.

She told E! News: ''I didn't follow any of the drama, but I think Jamie will be amazing.''

Ehle admits she didn't read any of the 'Fifty Shades' novels until after she was cast in the movie and is excited to be part of the blockbuster phenomenon.

She added: ''It's extraordinary. I'm excited. I feel kind of like a tourist ... I'm along for the ride, as it were.''

However, the actress admits she isn't sure how James' salacious novel will translate to the big screen in the movie directed by Sam Taylor-Johnson.

She said: ''Being a visual medium, it's hard to tell from a script what something's going to be like.''