MANCHESTER, England -- Ariana Grande hosted a three-hour-plus benefit concert for the victims of the bombing at her May 22 show at Manchester Arena.

The A-list roster, anchored by Grande, began with an emotional reminder of what brought everyone here.

The "One Love Manchester" concert was meant to honor the victims of the deadly bombing nearly two weeks ago, but the message on Sunday took deeper meaning and along with it a renewed fear in the wake of Saturday's attack in London.

Concertgoer Holly Thornton, 16, admits that she was a bit nervous to attend the concert. "I got butterflies and stuff like that," she said.

Thornton and Tia Larson, 16, and were at the Manchester Arena when the suicide bomber struck.

"I thought 'oh, she's come back on' -- and people screaming because she's on," she said, adding that the thought it was part of the celebration.

They are among thousands of people from the original concert who returned tonight in defiance, they say, of terror.

The concert featured pops biggest and brightest. It was upbeat but careful to never rise above the tragedy.

"What a better way to fight evil, with evil, than to fight evil with good. Don't you guys agree with that?" Justin Bieber asked the sold out crowd.

Fifty-thousand people packed the sports stadium just outside the city. Thousands lined up hours earlier to go through tedious but necessary security checkpoints. Everyone was searched. The hundreds of police on guard a reminder of the two active terrorist investigations still underway.

"When I see all the police, it reassures me that everyone is going to be okay," Larson said.

"We are still all together, we are not scared," Thornton added.

Inside, all eyes were on the stars. A celebration of music, defiance and uniting together. Ultimately it was the victims who were front and center, all the profits from ticket sales will go to the victims' fund, which has already raised more than $7 million.