Zac Efron Warns That People 'Really Should Pay Attention' to Their Friends: 'I Learned This the Hard Way'

The actor opened up to ET at the Tribeca Film Fest screening of his new film 'Extremely Wicked, Shockingly Evil and Vile.'

Zac Efron wants people to pay closer attention to the people they welcome into their lives.

The actor walked the red carpet at the Tribeca Film Festival screening of his new film, Extremely Wicked, Shockingly Evil and Vile -- in which he stars an infamous serial killer Ted Bundy - and he spoke with ET about the importance of picking and choosing your friends in a dangerous world.

"In a world where we swipe left and swipe right and you meet people, friends come and go, you really should pay attention to who you're with," Efron said, possibly referring to lessons he learned while researching the horrible crimes committed by Bundy during his life.

"I learned this [lesson] the hard way," Efron added, although he did not elaborate. "And hopefully nobody else has to."

Another thing Efron learned was how to get into the mind of the terrifying murderer he embodies in his dark and macabre biopic, which appears to be a feat that he accomplished masterfully, considering the slew of positive reviews regarding his captivating performance.

However, the 31-year-old star says he isn't paying much attention to critics or reviews.

"I think it's always nice to be acknowledged for any performance," he explained. "I don't really read reviews or anything like that, [but] I'm very happy [about] what [director] Joe Berlinger and I set out to do, which was to make a movie about something that happened in real life that wowed the world."

Efron went on to say that the most important thing for him and the director was to tell an accurate and enthralling story while at the same time making sure "not to celebrate the man… or his horrific acts."

The Tribeca Film Festival in New York runs from April 26 to May 5. Extremely Wicked, Shockingly Evil and Vile premieres on Netflix May 3.