LOS ANGELES — Conan O’Brien kicked off the 22nd annual MTV Movie Awards on Sunday night with a challenge to gain 50 celebrity cameos for his opening segment, a shtick with Will Arnett that merged two categories, best fight and best kiss, and a musical number about hating musical numbers in big awards shows.

Walking out to a track by rapper Rick Ross, O’Brien joked that he was almost injured by the show’s flashing pyrotechnics. “Fire, explosions and rap music: all things you associate with Conan O’Brien,” he joked.

Jared Leto took home the award for best on-screen performance for his role in “Dallas Buyers Club,” which was presented by Lupita Nyong’o.

“A year ago nobody knew my name,” quipped Nyong’o. “Now no one can pronounce my name.”

Furthering the speculation that Nyong’o and Leto are romantically linked, Leto, in a deep and suave tone, said, “It’s an award in itself to get that from her.”

Jonah Hill was awarded best comedic performance for “The Wolf of Wall Street.”

Leto presented Mila Kunis with the award for best villain for “Oz the Great and Powerful.” “You just made my 12-year-old self dream come true,” said Kunis while holding her golden popcorn prize.

Accepting the popcorn-shaped prize from Jessica Alba and Rita Ora for best shirtless performance for “That Awkward Moment,” Zac Efron hesitated to take his shirt off on stage until Ora ripped it open. He then finished the job and took it off.

Receiving this year’s trailblazer award was Channing Tatum. The first male to gain the honor after Emma Stone and Emma Watson, Tatum accepted the award from his “Jupiter Ascending” co-star Kunis and his “22 Jump Street” co-star Jonah Hill. Tatum admitted he thought he was being punked when he found out he would get the award.