MANSFIELD — Retired Mansfield Police Det. Dave Messmore knew he was on to something that chilly January day in 1990 when he approached the front door at 616 Hawthorne Lane in Mansfield.

He was there on a missing person case, looking for Noreen Boyle. But he found something else instead.

“There was a note taped on the door that said, ‘No one in this house is allowed to talk to the police,’ ” Messmore remembered. “In my line of work, that’s called a clue.”

That line brought down the house, and it was a sold-out house of 1,400 people on Saturday night at The Renaissance Theatre to see the hometown premiere of “A Murder in Mansfield.” Tickets are still available for a second showing on Sunday at 3 p.m. at The Ren to accommodate overwhelming ticket demand.

Messmore’s anecdote was shared during the guided panel discussion after the film. A similar session will take place after Sunday’s showing, too.

But the unquestioned star of the production, and the discussion was Collier Landry, the son of convicted killer Dr. John Boyle and the victim, his mother Noreen. Landry received standing ovations after the film and again after the discussion.

“I want to congratulate this young man,” said retired News Journal editor Tom Brennan, who shepherded the newspaper’s coverage of the case 28 years ago, and was also a guest panelist. “I talked with Dave (Messmore) before the film and we agreed, you’ll never meet a more courageous person. Courage is the word.”

Landry said it was long his dream to have the film shown in his hometown. A partnership between the Richland Source and the Renaissance Theatre helped that dream become reality.

“I wanted to heal myself, and I always wanted to do something positive with this tragedy,” said Landry, who was 12 when the case unfolded. “I wanted to explore the affects, the consequences of violence on communities.

“This gives me healing, a catharsis. It evolved into something greater than myself and I’m proud to share it with the community that showed me so much love.”

Oscar-winning director Barbara Kopple directed the film, and noted the important role Mansfield played in the story.

“As a filmmaker, particularly in documentaries, you can’t plan anything, you have to see where it goes,” Kopple said. “This community is so incredible. You guys have given so much of yourselves, so much love.

“I feel terribly blessed to be a small part of this community.”

Numerous times throughout the night Landry referred to the event as a tribute to his mother’s memory. It was clear the memory of the case was still strong among members of the audience. There was a line outside when the doors opened, parking was scarce and sold out signs were taped to the windows in front of the theatre.

The panel discussion and ensuing Q-A triggered a number of provocative questions and responses.

“The story quickly became something the entire community was following,” Brennan recalled. “It was a murder mystery but more than that it was a human-interest story that started with a prominent physician in town and included a body buried under a house in Erie, Pennsylvania.

“During the trial, people fell in love with Collier — a young boy being brave enough to get up there and testify.”

That testimony was crucial in Boyle’s conviction, and yet another aspect in a long and difficult father-son relationship.

Dr. Dennis Marikis counseled Landry during the film and was also a panelist. He was asked a number of times about grief and healing.

“The primary aspect of healing is more the process of accepting,” Marikis said.

In the climax of the picture, Landry confronts his father during a pointed exchange at the Marion Correctional Institution.

“Sometimes you just have to come to terms with this is who I am because of what happened,” said Landry, who dropped his last name Boyle years ago in favor of his middle name. “I found my resilience from this.

“This is about healing and moving on with your life.”

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