One Love Manchester: Ariana Grande calls benefit concert 'the medicine the world needs,' Justin Bieber pays emotional tribute to victims

Ariana Grande's One Love Manchester concert, a benefit for the victims and families of the May 22 terror attack after the singer's show at Manchester Arena, was live streamed on Sunday (June 4). Grande opened her much-anticipated performance with "Be Alright," but many of her music peers took the stage before she did.

Marcus Mumford greeted the crowd at the start of the concert, asking, "Would you please stand for a moment of silence?"

"Let's not be afraid," he added.

He opened the show with a solo performance of Mumford and Sons' "Timshel" before welcoming Manchester's own Take That to the stage. The group sang "Shine," "Giants" and "Rule the World," before which they urged the crowd to "stand strong, look at the sky and sing loud and proud."

Robbie Williams' set followed, starting with a version of "Strong" in tribute to Manchester. "Angel" came next, and both songs inspired loud sing-alongs from the audience. "For the last chorus, are you going to help me out?" Williams asked, but the question was unnecessary, as the crowd was doing a fine job of that already.

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"All our hearts are with you," Williams said. "All our hearts are with Manchester and with the U.K. So many of our friends in this great city, we're brokenhearted for parents who lost their children, children who lost their parents ... There is no end to grief. That's how we know there is no end to love."

Pharrell was next to take the stage, with a set list that began with "Get Lucky," his track with Daft Punk -- a song that even Miley Cyrus, spotted sidestage, was singing along to. Miley's presence on the stage soon made more sense: Pharrell invited her to join him for a song.

"Despite all the things that have been going on in this place, I don't feel or smell or hear or see any fear in this building," Pharrell commented. "All we feel here tonight is love, resilience, positivity. And you know what? I hate to be corny, but it actually makes me, uh" ... you can guess it: "Happy," featuring none other than Miley.

"The most important responsibility we have on this entire planet it to take care of one another," Cyrus said to the Manchester crowd after her performance with Pharrell.

"It's always felt like a home away from home to me," she said of Manchester, where she's performed multiple times. She then dedicated her brand-new song "Inspired" to the city.

Cyrus left the stage for Niall Horan to take over. The One Direction member launched right into his solo track "Slow Hands," then paid some love to the city: "I just want to say I've been lucky enough to travel all over the world, and every time I come back to Manchester, I'm addicted to this place." His debut solo single, "This Town," was then performed in tribute to Manchester.

Scooter Braun then introduced "one of the bravest people I know," the woman of the hour: Ariana Grande. She opened her set with a resilient "Be Alright" and went straight into "Break Free," which concluded with thunderous cheers and streamers falling from the sky over the crowd.

The live stream then offered an unexpected interlude from Stevie Wonder, who appeared for a brief performance of "Love's in Need of Love Today." Following Wonder, Little Mix brought the harmonies to the show with their empowering song "Wings."

Grande returned to the stage with duet partner Victoria Monét for "Better Days," and stayed on stage to join the Black Eyed Peas on "Where Is the Love?"; Grande and the group held up heart signs for the crowd before the singer announced, "I want to take a moment to introduce the next performer, who's been my idol since I was 11 years old."

Imogen Heap sat at the piano for a stirring performance of "Hide and Seek."

The ballad was followed by a full children's choir, fronted by Grande, singing "My Everything."

Mac Miller was the next guest to take the stage, joining Grande on her track "The Way." Grande then served vocals on Miller's own "Dang!"

The love continued as Grande's friend Miley Cyrus came to the stage again: the two pop stars embraced with a big hug, and Cyrus hinted, "We've done this song together before." They sat down together for a cover of Crowded House's 'Don't Dream It's Over."

Following her duet with Cyrus, Grande spoke emotional words to her audience: "I love you so, so much. Thank you so much for coming together and being so loving and strong and unified. I love you guys so much, and I think the kind of unity you're displaying is the medicine the world needs right now."

The singer revealed that she talked to the mother of Olivia Campbell, a young victim of the Manchester bombing, who informed her that the teenaged fan would've wanted to "hear the hits." Grande admitted she changed her whole set list in light of this, just before performing "Side to Side."

Grande left the stage once more as Katy Perry took her place. "Thank you, Ariana, so much, for your incredible courage and strength and for inviting me to participate," Perry said.

"It's not easy to always choose love, is it?" she continued. "Especially in moments like these. It can be the most difficult thing to do. But love conquers fear, and love conquers hate. And this love that you choose will give you strength. It's our greatest power."

She encouraged the crowd and viewers to take part in an exercise: touch the person next to them and say, "I love you."

Perry's first song was "Part of Me," and an energetic performance of "Roar" followed.

If the crowd hadn't gotten loud enough yet by this point, Justin Bieber strolling out to the stage brought it to a whole other level.

Addressing the audience, Bieber declared, "What an amazing thing we're doing tonight, would you not agree? Would you agree that love always wins? What better way to fight evil than to fight evil with good."

"It's an honor for me to be here. And maybe I should just play some music, right?" he said before showing off his musical chops with a stripped down performance of "Love Yourself" on acoustic guitar and leading fans in a chant of "Love. Love. Love. Love."

Up next was another song on acoustic guitar: Bieber's solo take on "Cold Water," his collaboration with Major Lazer.

"God is in the midst," an emotional Bieber said. "No matter what's happening in the world. And he loves you. And he's here for you. I just want to take a moment to honor the people who were lost, who were taken. We love you so much. To the families, we love you so much ... put your hands up to honor them."

After Grande once again took the stage for another one of her hits, "Love Me Harder," a series of famous faces appeared on the screen to say "I stand with Manchester," including Halsey, Demi Lovato, Camila Cabello, the Chainsmokers, Kendall Jenner, Kings of Leon, Paul McCartney and more.

Coldplay's Chris Martin soon joined Grande on stage to perform a cover of Oasis' "Don't Look Back in Anger," dedicated to Grande -- "from us to you" -- to the delight of the crowd. He knelt in front of them, at the edge of the stage, as Coldplay played "Fix You," then bounced around the stage during "Viva la Vida." Confetti fell on the band and fans as "Something Just Like This" was performed.

And next, to the surprise of all, Liam Gallagher graced the Manchester stage for Oasis' "Rock 'n' Roll Star," the opening track from the English rockers' debut album, just before breaking into his new solo single, "Wall of Glass." Chris Martin came back out to assist Gallagher on a poignant performance of Oasis' "Live Forever."

Closing the concert, Grande brought the all-star lineup to the stage as she belted "One Last Time," which has been re-released on iTunes as a charity single to benefit the victims and families affected by the tragedy in Manchester. She barely held back tears as she hugged the artists who had come out to show their support.

A beautiful, earnest performance of "Somewhere Over the Rainbow" by Grande closed the night.