Denzel Washington has admitted that he didn't initially jump at the chance to star in his latest film, Safe House.
The double Oscar winner plays the CIA's most dangerous traitor in the movie, opposite Ryan Reynolds.
But the actor said he didn't think the early version of the script was good enough.
"This was one of the last films my late agent Ed Limato really wanted me to do, so I wanted to do it for that reason alone. But I wasn't that impressed with the screenplay," he said.
"Then before I met the director Daniel Espinosa, they showed me his film Snabba Cash (Easy Money) - and he's such a brilliant young filmmaker that I was very excited about the opportunity to work with him. If I hadn't met him, I probably wouldn't have done this movie. It didn't interest me and I didn't think it was that good."
Denzel then signed up for Safe House after it was agreed he could work on the screenplay.
"I enjoy helping to develop material and I've been doing it for 20 years or more. I'm a logic master. If things don't make sense, I have to make them make sense," he said.
Denzel said of helping to hone the script over four months: "It took us a long time but it was also a way for me to get into the part and figure out my character."
:: Safe House is in cinemas now.