The Requiem for a Dream filmmaker discussed trying to sow the seeds of discontent between the two actresses of his 2010 ballet horror-drama in an interview with Vogue celebrating the 15th anniversary of the film.

"I was trying to be a sneaky director and make them argue," Aronofsky remembered. "Mila and Natalie both realized very quickly what I was doing and made fun of me, so it quickly became a joke that we all understood. They're both very clever and were instantly privy to whatever trick I was playing."

In the same interview, Portman and Kunis both reflected on Aronofsky's unusual strategy for crafting onscreen tension. "I remember being separated from Mila and that we weren't in the same space a lot when we weren't shooting," Portman recalled. "Darren made some comment early on, like, 'Ya know, Nat, Mila's dancing so well.' And I was like, 'Of course she is! She's so f---ing talented and I love her so much and I'm happy she's doing a great job!'"

Kunis said she immediately saw that Aronofsky's lies didn't add up. "Darren would tell me, 'Nat is working really, really hard. She's not even taking Saturdays and Sundays off,'" the Forgetting Sarah Marshall actress remembered. "Then I would text Nat and she'd be like, '...No, I'm not?' I think that's how we figured out what Darren was up to, but it was all in good fun."

It should come as no surprise that Portman and Kunis were chummy on set, as the Star Wars actress was the one who recommended Kunis for the movie in the first place.

"We had been friends for years and I remember being at the Rose Bowl Flea Market with her, talking about this ballet movie I was making with Darren," Portman remembered. "Mila said, 'I remember when I would take off my pointe shoes...' and I was like, 'Wait, you did ballet?!' I immediately called Darren and said there was this amazing actress with ballet experience who would be perfect for Lily."

And despite Aronofsky's trickery, Kunis had nothing but praise for the filmmaker. "Every journalist wanted to know how scary Darren was: 'How intense was his set? How intense was he?'" she recalled. "I would say, 'He's actually a really kind, lovely guy who took us to see Twilight one time because we had the day off.' And journalists were always so disappointed that he wasn't some tortured soul who treated us like garbage."

Portman, who won an Oscar for the film, agreed. "Black Swan was deeply challenging but it was a wonderful experience," she said. "Our set wasn't silly, but everyone was kind and respected one another."