09/17/2016 11:49 EDT | Updated 09/18/2017 01:12 EDT

Global Citizen: musicians join forces in free concert to combat deadly diseases

Long before local band Half Moon Run'sConner Molander became famous, he knew he would one day like to perform for a cause. The indie rock band member is excited to be one of the headliners at the Global Citizen concert in Montreal, to help stop the spread of AIDS, malaria and tuberculosis.

They join international stars Usher, Metric, The Roots, Sam Roberts and more for tonight's show at the Bell Centre.

Molander said the band wanted to give something back.

"We're in the business of making music but now there's a responsibility to be just a bit more educated about things like this," Molander said.  

Global Citizen is the group behind the show, which calls itself a social action platform that pushes government leaders to invest in solving some of the world's biggest problems. 

Most of the 13,000 tickets for Montreal's show were free, but only given out to fans who agreed to perform social media actions for global health.

Concert-goers had to watch a video about AIDS, leave a voicemail for the Prime Minister about health, email world leaders about polio and sign two petitions: one on education for girls and the other on fighting diseases.

Molander was surprised how quickly the free tickets were snapped up and he's happy so many fans were willing to engage on social media for a good cause. 

"I'm pleasantly surprised and if people can increase their ability to pay attention to things like this, it shows a brighter side to the future that we're facing," says Molander.

The concert takes place one day after the Global Fund's pledging conference in Montreal, where members of government and the private sector commit to funding efforts to end some of the world's deadliest diseases.

Global Citizen says for the past five years, people around the world have taken more than six million actions to solve some of the world's biggest challenges.

"They are doing caller campaigns to Prime Minister Trudeau. They are signing petitions, doing email campaigns, doing petition campaigns and they are lending their voices to help solve these big issues," says Dominic Mishio, Canada's director for Global Citizen.  

Mishio says global leaders have made 120 commitments and policy announcements, which adds up to financial aid of over $25 billion. Global Citizen says it has a goal to end extreme poverty by 2030.

There are still tickets available for the concert at the Bell Centre, but they come at a price between $87 to $150.

Following the concert in Montreal on Sept. 17, New York's event takes place a week later with performances from Rihanna, Chris Martin, Metallica, Eddie Vedder and Kendrick Lamar.