Josh Hartnett Brands Taylor Swift’s Fans as Hardcore as ‘Over-the-Top’ Music Nuts in His New Serial Killer Chiller

Josh Hartnett has branded Taylor Swift’s fans as nutty as the obsessed music crowd in his new serial killer thriller Trap.

RadarOnline.com can reveal the 47-year-old actor got overwhelmed when he joined throngs of Swifties for one of Taylor’s sold-out Eras Tour gigs in London with his daughters.

The show came after he’d wrapped playing a serial killer father in 53-year-old M. Night Shyamalan's new chiller, which sees his bloodthirsty character take his daughter to a huge concert by fictional pop star Lady Raven – where he is told the FBI are hunting him.

Hartnett said he thought the crazed fans shown in Trap were over-the-top – until he saw the heaving mass of Swift’s disciples in London.

The actor added about what he called the “mania” surrounding Taylor: “Some of the stuff, while we were filming Trap, I was thinking, ‘God, this is a little over the top. The amount of the fervor of the audience, and they know every word’. Then I went to the concert. I was like, ‘No, it’s exactly right.”

Hartnett has four children with his actress wife, Tamsin Egerton, 35, the eldest of whom turns nine later this year.

He said preparing for Swift’s gig meant repeatedly listening to her tunes with his girls for six months, adding: “The thing is, my kids weren’t really into pop music so much last year when we shot Trap."

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He told People: “Then when they heard the Eras Tour was coming because their friends at school were all into the concept, they just immediately became Swifties – and really hardcore Swifties."

“We listened to that music for six months non-stop in the car before we went to the show. The album that they play a lot at our house is ‘1989’, and I like that album. It’s a good album.”

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