Sooner or later every fairy tale reaches its happily ever after. For Shrek, the long-running animated fantasy franchise about a curmudgeonly ogre (voiced by Mike Myers), his human-turned-ogre wife, Fiona (Cameron Diaz), and his pals Donkey (Eddie Murphy) and Puss in Boots (Antonio Banderas), that time is now. On Friday, DreamWorks Animation and Paramount will release Shrek Forever After, the fourth — and, the studios say, final — installment in the series, in which the titular green guy is thrown into an alternate version of his Far, Far Away kingdom where he never existed and life turned out much differently for his pals. Before the storybook shuts for good, Dave Itzkoff asked some of the Shrek stars about the series and what its ending means to them. These are excerpts from the conversation with Cameron Diaz. Full interview can be read here.

Cameron Diaz, Princess Fiona

Q. Did you have an appreciation for cartoons before you started working on “Shrek”?
A. I grew up on the barest of cartoon animation. I grew up with Tom and Jerry and the Road Runner and Wile E. Coyote. All the great, violent, sardonic characters of the good ol’ days.

Q. Those characters seem much more aggressive than you.
A. Good. You don’t know me. [Laughs.]

Q. Did it take any extra convincing for you to make all the embarrassing bodily noises that Princess Fiona is called upon to produce?
A. Well, I’m just basically a 14-year-old boy in my heart, in my spirit. So it’s very easy for me. It doesn’t take a lot of prodding for me to make silly noises.

Q. Have you ever been recognized in public for your “Shrek” character?
A. People say all the time to me: “Oh, you’re Cameron Diaz. There’s Cameron Diaz.” But of all the characters that I’ve done there’s only one that I really get, and that’s Fiona. That’s the only time people say to their kids, “This is Princess Fiona.” And I’m always like: “Don’t tell them. Just let them live as if Princess Fiona exists as a real ogre. Don’t take that away from them.”

Q. What does it mean for you that the “Shrek” series is coming to an end?
A. I realized it’s been a sort of safety net. It’s been a decade of knowing that you finish one and for the next two years we’ll be making another one. To think that that next phase of the story isn’t being told — I’m still crossing my fingers that maybe one day it will be.

Q. What’s changed about your life during that time?
A. I think that I’m definitely more mature. In some ways. I finally turned 15.