There's a thin line between love and hate — and sometimes there's no line at all. That's one of the themes in Angelina Jolie's upcoming movie By the Sea, costarring her husband, Brad Pitt. The actress-director, 40, gave Vogue a behind-the-scenes peek at the movie on Friday, Oct. 16 — and it looks like one heck of an emotional roller coaster. 

"Everybody knows that there is never just the tragedy of life or the humor of life or pure joy of life," Jolie, who has six kids with Pitt, says in the clip. "Relationships have those extremes. You can absolutely madly love the same person you want to kill."

Adds her husband, 51: "It's the puzzle of figuring out those things that get in the way of really loving someone. A lot of it's the past, a lot of it's insecurities, a lot of it's wanting something so much that you focus too much on losing it."

By the Sea — which Jolie wrote, directed, and stars in — is a romantic drama about a couple in the 1970s who are struggling to save their marriage. It's also the first film Pitt and his superstar wife have worked on together since 2005's Mr. and Mrs. Smith

Lest you think the movie is some kind of veiled commentary on the couple's own marriage, however, Jolie told Vogue it's not autobiographical. "Brad and I have our issues," she told the mag, which features her on its November cover, "but if the characters' were even remotely close to our problems we couldn't have made the film." 

Indeed, while Jolie said the movie took them out of their comfort zone and wasn't "the safest idea," Pitt says in the above featurette that it was a safe set. 

"We can experiment and play," he says of filming. "It's oddly a safer environment than any set I've been on before. So we let loose." 

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