Paul Dano has been traditionally one of the more private actors in Hollywood.
That was before he appeared in a the quirky romantic comedy Ruby Sparks with real-life girlfriend Zoe Kazan, who wrote the screenplay.
The lines became blurred in the indie gem which caused critical sparks to fly when it came out this summer, (it's now out on DVD and Blu-Ray)
No problem, especially since the movie was directed by husband and wife team Jonathan Dayton and Valerie Faris -- who had directed Dano in Little Miss Sunshine.
Dano says there was never any issues with all the couple-dome on the set.
"I probably tried to have a few boundaries that I am sure did not hold up with Zoe." he says. "I know I wanted to keep separate us as a couple while we were at the workplace. I do not know if we kept that up."
The toughest part was coming home at the end of the day and not constantly talking about what just happened at work.
"The hardest thing about working with your partner is that the work starts to become first," says Dano. "You are there 12-14 hours a day five days a week and it's the biggest thing on your mind all day. When you go home, you have to put the day away."
And Dano didn't mind that people might suspect the story about a struggling screenwriter, Calvin Weir-Fields, who creates and then controls his own dream girlfriend, might have some basis in relational reality.
"I realized some people were thinking how much of this was me?" says Dano. "I think there are qualities we share in common. But there are lot of parts of other people in Calvin -- parts of Zoe, ex-boyfriends of Zoe. If Zoe had written us, we wouldn't have done the film together. It would have been boring to us."
Don't expect Dano to crank out the typewriter, like his character, and write his own screenplay.
"I am baffled by good writing," says Dano. " I'll give it a shot I'm sure. But no plans right now."