Michael Franti remembers exactly where he was on that fateful Sunday last Oct. 1 when a lone gunman opened fire on an unsuspecting crowd of thousands attending an outdoor music festival in Las Vegas.

Franti was 400 miles away, playing to an open field of thousands of fans at the Oro Valley Music Festival. And there, for the grace of God, he recalled, it could have been him and the half-dozen other bands on the Oro Valley festival lineup.

Hours after the Vegas shooting, he and Train frontman Patrick Monahan sat backstage in a state of near disbelief.

“It was a horrible tragedy and we were devastated by it, but we were thinking ... this could have happened at our festival that day or at any one of our shows at any time,” said Franti, who returns to Tucson for a show at Rialto Theatre on Friday, June 8. “And we both echoed to each other that we are surprised it didn’t happen sooner. We live in this world that is challenged by violence on a daily basis.”

But Franti believes all it takes to change the culture is one voice, one action. And that one voice could be multiplied by millions until that one action becomes millions.

It’s all part of his “Stay Human” philosophy, laid out in a documentary of the same name that he made that is now making the festival rounds. The film traces the lives and actions of several ordinary people Franti has met along his world travels who are doing extraordinary things to improve the world.

“They remind me of what it means to be human and then how to stay that way, how to hold our dignity and our pride and our ability to connect with others when it feels like the whole world is falling apart,” Franti explained during a phone call from a Colorado concert stop last week. “I realized that the world actually isn’t falling apart, that if we just focused on the news all the time it might feel that way, but if we take moments to connect with other people, there’s actually billions of people doing billions of good things every day in billions of corners of the world … so that it will be livable for everybody.”

This month, Franti will release “Stay Human 2,” an album of songs inspired by the film. The record includes “Flower In the Gun,” a song he co-wrote with 19-year-old singer-songwriter Victoria Canal that addresses little things we can do to minimize violence in the world. Canal, who Franti said he discovered on Instagram, is opening for his “Stay Human Tour” including his Rialto show on Friday.

Franti called “Stay Human” a “very emotional film,” but one that will leave audiences inspired.

“It’s a 90-minute commercial for optimism,” Franti said with a chuckle. “I believe in realistic optimism. I don’t go, ‘Hey if I go and play LeBron James one-on-one, I’m going to win.’ But if I play LeBron James one-on-one, I’m going to learn a lot about myself and I’m going to learn a lot about basketball. I approach every thing in my life from that perspective of having optimism.”

Contact reporter Cathalena E. Burch at cburch@tucson.com or 573-4642. On Twitter @Starburch