The summer that Lupita Nyong’o spent filming her zombie romantic comedy Little Monsters in Sydney was one of the hottest on record in Australian history.

Nyong’o and co-stars Josh Gad and Alexander England battled their way through the sweltering elements while making this horror-comedy about a Kindergarten teachers whose school excursion to a sleepy farm is undone spectacularly by an invasion of marauding zombies.

Little Monsters has just premiered to rave reviews at the Sundance Film Festival, with many praising Nyong’o as “so good”, “pure gold” and “a beacon of movie star charisma” in the film.

The movie also features a particularly memorable scene in which Nyong’o’s character Miss Caroline strums out Taylor Swift’s Shake It Off on a ukulele to calm her class down in the middle of a violent zombie rampage.

The moment was particularly powerful for the actress because of the importance of that song in her life. “Shake It Off means a lot to me,” she told audiences after a screening of Little Monsters at the Sundance Film Festival.

When the song first came out, Nyong’o was struggling through a difficult period in her career while working on location away from her family and friends. “I was going through a hard time professionally and I was just in a funk,” Nyong’o recalled. “I was working abroad and my best friend came to cheer me up.” 

Her best friend’s prescription for self care was a hefty dose of Taylor Swift’s ebullient, exuberant hit Shake It Off. “He played Shake It Off on his phone, and we just had a dance party in my bedroom,” Nyong’o recalled.

“It meant a lot to me that this film had that [song],” Nyong’o said. “And so when I heard that they were having a hard time [getting the rights] I wrote Taylor Swift myself and asked her, and told her that story. And she said yes!”

In an interview with USA Today, Nyong’o added that singing on camera was more terrifying to her than any of the stunts involving armies of undead. 

“I was very nervous and I’m very nervous now, just knowing that people are hearing me sing makes me very shy,” she said. “I do enjoy singing but it’s not often that I do it in the movies. It was a weird feeling. But I learned to play the ukulele as well, so it was all really uncharted territory.” 

It helped that the song she got to sing was a song that was so close to her heart.

“Honestly, Shake It Off is an anthem of mine,” Nyong’o said. “That’s one of the reasons why my interest was piqued in this movie when I read the script, because I was like, ‘Someone else who loves Shake It Off just as much as I do!’” 

Images: Getty