By the early 2000s, some people in Boston had heard whispers about priests in the area who molested children, and about efforts by the Catholic Church to conceal the crimes.

“There were a lot of people who knew a little bit,” says Josh Singer, co-writer of the fact-based “Spotlight.”

In the film, Singer and co-writer/director Tom McCarthy show how grueling it was to get to the rest of the story.

The movie, which opens locally Friday, is named for the investigative team at the Boston Globe that in 2002 exposed dozens of area priests who had sexually abused children and the subsequent cover-up that reached the highest echelons of the Catholic Church.

“Spotlight” isn’t so much about the priests or even the Globe’s final story — it’s about the painstaking legwork that eventually resulted in the Pulitzer Prize-winning coverage. Singer and McCarthy had to piece together their movie the way the Spotlight team pieced together its story.

“We had to go back to [the team] again and again and again. Not everyone wants to open up and share their story, even when they’re proud of it,” McCarthy says. “Sometimes it took us having these conversations over and over again and each time we’d get a little bit more. The reporters were the ones who identified that and said, ‘You guys are doing what we do.’ ”

That also extended to their search through the Globe’s archives to trace how the story unfolded. (The filmmakers used a digital system; in the movie, the reporters use actual news clippings retrieved by the paper’s librarians, which are both things that used to exist.)

“We literally started going back through the clips and saying, ‘How was this story played with but not gotten [right away]?’ ” Singer says. “It turns out there were a bunch of things floating around. You’ve got all sorts of beat reporters and they’re running hard and stuff falls through the cracks. It was interesting to see what the bits and pieces were.”

A key goal of the film was showing how successful journalism can be when journalists are allowed to take their time and pursue a story.

“We wanted to show, in the wake of what’s happened in journalism in the last 10 to 15 years, what journalism was like in that day,” Singer says. “And what it still can be.”

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