When a bomb was detonated at Ariana Grande's Manchester concert in, Mendes happened to be in London. "There was the attack on the bridge, and I remember that day thinking, like, 'OK, I gotta text [Khalid],'" he recalled. "When I texted him, I said, 'When we get together, we have to make a statement. We have to move. We have to write about what's going on in life and how the youth is feeling because I think we have the voice to do that.' We got together that day and I was like, 'This is a huge task.' Because you're always terrified going into a session knowing like, 'OK, this is going to be a big session. I have one day. Is it going to be the greatest song or not?'"

"I remember I woke up in the morning and the whole thought of my youth trying to be taken away from me [was overwhelming]. Not youth as in my age—youth as in my love, my happiness, my joy, my purity. It's not even about age; you could be 50 and your youth is there. It's in you. And all of these horrible things happening in the world, all of the headlines, it felt like every day it was just being pulled more and more out of us," Mendes explained. "I was like, 'This is what we have to write about.' And It was awesome. I'm really, really proud of the song."