Dakota Johnson made her parents ''promise'' not to watch the 'Fifty Shades' movies.

The 27-year-old actress - who is the daughter of actors Melanie Griffith and Don Johnson - admits it is ''hard'' for her mother and father to know they'll never see her in the raunchy high-profile trilogy, but she is thankful they agreed to her request.

Asked if they have seen the films, she said: ''No, that is not happening, nor will it ever happen. That's hard for them, just this huge moviement around these movies that I'm part of, but not being able to watch them.

''I know it's tough. But I made them promise and they respect that.''

And Dakota will be particularly thankful her parents won't see 'Fifty Shades Darker' because it's even raunchier than 'Fifty Shades of Grey' was.

She told OK! magazine: ''The sex is definitely better in this one. [My character] knows more what she wants. She's more confident now and has an understanding of what's making him tick.

''Their connection is stronger, emotions are deeper. That makes sex better, doesn't it?''

The final instalment, 'Fifty Shades Freed' was shot at the same time as 'Fifty Shades Darker', so Dakota is going to miss working so closely with Jamie Dornan - who plays Christian Grey to her Anastasia Steele - and hanging out with his wife Amelia Warner and their daughters Dulcie, three, and 12-month-old Elva.

She said: ''Jamie is my dream partner and supported me. I've supported him.

''It's a lot to ask of two people, of two actors, to take on these highly emotional, sexual situations, but I think we've done us proud.

''He'll be my friend for the rest of my life. I adore him, I adore his wife and his gorgeous babies. They're the most perfect little family unit.

''That was probably the best part of the shoot, getting to hang out and play with them So cute.''