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Bradley Cooper stars in the upcoming drama The Words with his former girlfriend Zoe Saldana, and although the two are no longer dating, he revealed that he enjoyed that experience and praised the quality of her acting.

"Zoe's an incredible actor," Cooper gushed of Saldana, who he dated during filming. "Actually, when she came on...the relationship (between their characters) was not as plot-driven as it became once she came on. So, we actually changed a lot of the major plot changes that occurred because of how committed [she was] and what truth she brought to the project."

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Cooper was interviewed with director Brian Klugman, who is a close childhood friend of his that he has maintained over the years. The 37-year-old Philadelphia native marveled at the fruition of their film project together.

"We found a similar love for film...it was hard to find guys that loved film as maniacally as we did," Cooper reflected of their initial connection as friends. "He moved out to L.A. eighteen years ago and I went out there as soon as I could and slept on his couch. So, the fact that we made a movie together is insane."

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The project, which revolves around Cooper's character's experience with plagiarism, delves into the realms of ontology, as the viewer is confronted with deciphering reality.

"It's a story within a story within a story, actually," said Dennis Quaid, who will star in the upcoming drama-western Vegas this fall. "You as the audience member are trying to decide what is real-life and what is fiction, and you ask that about your own life in the process."

Ben Barnes, who plays a younger version of Jeremy Irons' character, maintains that the film is left up to subjective interpretation, which creates an interesting dialogue about the plot.

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"Even if you can't relate to the plagiarism...you can still relate to the relationships and the passion," said Barnes, who is best known for playing "Prince Caspian" in The Chronicles of Narnia. "People have different ideas about which characters are real and which aren't [and] which characters are older versions of others and which aren't. I think it's O.K. to have that debate."

The Words is in theaters September 7.