"Support you local newspapers is one of the takeaways from this whole thing," Slattery tells PEOPLE of his new film Spotlight

By Michael Miller
Updated September 15, 2015 08:00 PM

Playing one of the real-life reporters who broke the Catholic Church’s child molestation coverup story completely changed John Slattery’s view of investigative journalism.

“It enlightened me to how news is gathered,” the Mad Men actor exclusively told PEOPLE at the Toronto International Film Festival, while seated next to his costars Liev Schreiber and Brian d’Arcy James.

“It also made it clear what a shame it is that newspapers, especially local papers, don t have the resources to commit the people and the time to long term investigative journalism.”

In Spotlight, Slattery plays Ben Bradlee Jr., one of the Boston Globe reporters who uncovered widespread instances of child molestation and cover-up within the local Catholic Archdiocese.

After learning about the hoops that Bradlee Jr. and his fellow reporters were forced to jump through to tell their story, Slattery says he realizes, “how important [it] is to the balance of a society to keep an eye on what needs to be watched, and for people s stories to be told and for truth to be uncovered.”

He adds, “It s difficult for papers. Support you local newspapers is one of the takeaways from this whole thing.”

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James noted that accurately representing the process of reporting a story was equally important as developing their individual characters.

“It was important to get not only the people that the actors are portraying right, but the world in which these people live, and how they tell the story, and the politics of editing, and how a story is vetted and how a story eventually ends up on printed page.”

Schreiber adds that he was struck by the camaraderie among the reporters. “I was really impressed with their generosity towards each other,” he says.

“It has the potential to be a very heroic story, and one might want to claim credit here or there, but to a man they all sort of pushed it over to the other, which was remarkable to me.”

Spotlight opens in theaters Nov. 5.

For full coverage of the 2015 Toronto Film Festival – including the hottest premieres, the biggest stars and the buzziest films – check out people.com/tiff, instyle.com and ew.com