Local filmmaker Matt Gallagher is putting the finishing touches on his documentary, "Dispatches from a Field Hospital", which is set to premiere on TVO on March 16.

The doc takes a unique approach to examining the COVID-19 pandemic — it showcases correspondence between patients at the St. Clair College SportsPlex field hospital and their loved ones.

Windsor Regional Hospital set up the field hospital in April of 2020 to treat COVID-19 patients. The last patients were discharged in June.

Gallagher initially wanted to shoot a doc from inside the hospital. He then had the idea to explore the pandemic through "dispatches" — conversations the field hospital patients had by phone and through iPads.

"With documentaries, access is everything, and so you're always trying to figure out the best way to tell a story," Gallagher told Windsor Morning host Tony Doucette Thursday.

"I started to understand that there's another way to tell this story, and that's when [I had] the idea of telling the story through these dispatches, through all the the communications that were coming out of that field hospital from patients to their loved ones on the outside."

Gallagher had wanted to do a documentary on the field hospital since it opened. What he didn't expect was that the project would become a deeply personal one — his father, Morrie Gallagher, tested positive for COVID-19 and was transferred to the field hospital soon after it opened. He was one of 50 patients transferred to the hospital from Heron Terrace long-term care home in Windsor.

That means his parents, and in particular their phone conversations, have a starring role in his film. But the pandemic meant that Gallagher and his team could not film in a conventional way.

"We couldn't film in people's homes. We couldn't have any contact with them, so we had a rule — a strict production rule — where we had to change the way we made a film," he said. "So a lot of the filming that I did, with my mother in particular, was filmed through the front windows of her house."

Four other families and their conversations with patients, all of whom were also residents of Heron Terrace, are featured in the documentary.

Gallagher says through these conversations, different themes emerged — in particular, touch.

"These dispatches from the field hospital, all these communications through iPad and through the phone, it was great to sort of be able to see your loved ones. But what can't be replaced is this touch," Gallagher said.

"And so touch is a very prominent theme in the documentary. I mean, everyone I spoke to talked about it."

The families aren't the only characters in the documentary. Once patients left the hospital in June, Gallagher also had the opportunity to interview staff in the empty complex.

Gallagher said talking to the staff in a place where they had spent months taking care of patients created a powerful moment.

"Right from the doctors to the nurses to even the guy who did the housekeeping," Gallagher said. "This documentary is about all these communications, but it was the staff who made it happen."

Gallagher says his father, who has dementia, is now back at Heron Terrace, and Gallagher's mother is now able to see him as an essential caregiver.