Ethan Hawke kept his Taylor Swift video cameo (and “Dead Poets Society” reunion) secret from teen daughters

Hawke reunited with Josh Charles on the set of Swift's Post Malone-featuring "Fortnight" single from "The Tortured Poets Department."

Ethan Hawke had to watch his mouth (like a hawk, one might say) to remain tight-lipped about his cameo in Taylor Swift's new "Fortnight" music video with Post Malone and the actor's Dead Poets Society costar Josh Charles.

"We got this call [that] Taylor's releasing an album, The Tortured Poets Department, and I think she wanted to hide a little Easter egg about Dead Poets Society," the 53-year-old told Stephen Colbert of being cast in the video alongside Charles on Monday's Late Night episode. "You can't imagine what it's like to walk through an airport with a friend you've known for 35 years, that you grew up with, and watch all the young people in the airport with their Eras sweatshirts on and their Taylor Swift things, and we've got something on them. We're going to meet the queen ourselves!"

Hawke said the pair felt "like the biggest rock stars in the world" on the set of the video, which saw them play researchers at a fantastical clinic in the black-and-white video for Swift's Torture Poets Department lead single.

Related: The best Taylor Swift song from each album

When Colbert asked if Hawke spilled the news to his teenage daughters before the video dropped, Hawke confirmed that he "signed an NDA" and couldn't reveal the information even to his family.

"I tell my teenage daughters that I'm going to meet Taylor, and everybody at school is going to know," he said, laughing. "When they did find out, the look on their face was one of profound disappointment. 'Don't pay attention to my dad, my dad's an idiot, you should be calling me.' Taylor belongs to them, you know? I can't have that on them. I had to low-key it."

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Hawke and Charles first starred together in director Peter Weir's Robin Williams-starring 1989 classic, with Dead Poets Society going on to amass over $235 million at the global box office following its release.

In a 2014 interview with Entertainment Weekly for the film's 25-year anniversary, Charles credited the production with opening up a new chapter in his career as well as charting his friendship with Hawke.

"The movie almost got made the year before with a different director [Revenge of the Nerds’ Jeff Kanew], so Ethan and I met at the audition for that. We screen-tested together with other actors, and then the movie fell through, and there was a whole other year to wait, not knowing if it was even gonna happen again or if we were gonna [get recast]," he said at the time. "I got to work with Peter Weir and Robin Williams and make a film that has an iconic quality to it that people respond to again, and again, and again. I got to go to Europe for the first time [laughs], and room with Ethan while we were debuting at the Venice Film Festival, and walk down the red carpet at the Venice Film Festival, and have a standing ovation and be 18. It did a lot of things for me that go beyond the actual making of the film. It was a lot of my college—seeing the world, seeing that there’s so much out there."

Related: Every Taylor Swift album, ranked

Watch Hawke discuss his "Fortnight" cameo with Swift above.

Read the original article on Entertainment Weekly.