EXCLUSIVE: Alexander Skarsgard Jokes That His Frustrating Diet Inspired His 'Tarzan' Call

The Legend of Tarzan took over Hollywood Boulevard for the red carpet premiere on Monday, and ET was there for all the madness!

The Legend of Tarzan stars took over Hollywood Boulevard for their red carpet premiere on Monday, and ET was there for all the madness!

Margot Robbie had to employ her acting skills on the red carpet by pretending to be comfortable in the 95-degree heat while wearing a long-sleeved kimono.

WATCH: Alexander Skarsgard and Margot Robbie Talk Animalistic Love Scenes in 'The Legend of Tarzan'

"Not warm at all," Robbie kidded. "I'm absolutely sweating, but no, I'm all good."

Robbie's immense self-control in the California heat, mirrored that of co-star Alexander Skarsgard on the set of the film.

In the action-adventure movie, the former True Blood star plays the titular character, who is called back to his former home in the jungle after acclimating to life in London. Tarzan's presence is required to investigate the activities at a mining encampment.

WATCH: 'Frozen' Director Seemingly Confirms 'Tarzan' Fan Theory

To get in shape for the role, Skarsgard had to keep to a strict diet, which he joked came in handy with his signature Tarzan call.

"My trainer was like, 'You're going to get pasta for lunch,' and then I'd open the box and it'd be broccoli, and then they recorded the 'No!'" he joked.

But Skarsgard wasn't the only person on set with a great primal yell. Co-star Samuel L. Jackson showed off his impressive pipes for ET as well. Watch the video to hear!

The Legend of Tarzan opens July 1.