As a camera pans, three Boston firefighters sit in front of a wall plastered with images of their fallen comrades.
Their colleagues did not perish in a rampaging fire or in a sundered building.
They all succumbed to cancer.
Their stories were on full display during a screening last week of a new, emotional video on the toll cancer has exacted on Boston's firefighting force. Since 1990, more than 160 Boston firefighters have died from the disease, fire officials said, and every year, 20 firefighters are diagnosed with cancer.
"The first thing that went through my head when the doctor said I had cancer was that, 'I'm going to die,' " Firefighter Mark Matthews says in the video. "The question I asked him was: 'When?' "
The video shows women posting on the blank wall pictures of their husbands lost to cancer. A firefighter tearfully recalls a colleague buried close by. Family members hold the uniform hats of their loved ones.
"It's killing our members, simple as that," Commissioner Joseph E. Finn says in the video. "The one thing that is going to kill firefighters more quickly than a building collapse, more quickly than getting trapped — it's cancer."
The video is part of Finn's appeal to the city's 1,400 firefighters to always wear their protective gear — including hoods and air masks — even as a blaze retreats and begins to smolder. Chronic exposure to heat and smoke toxins leaves firefighters vulnerable and at risk, officials said.
Finn commissioned the documentary, produced by Embryo Creative of Boston, as part of his safety, health, and wellness campaign. He also called on veteran members of the Fire Department living with cancer to help him.
The commissioner held a private screening at Florian Hall — the home of Boston Firefighters Local 718 — on Thursday with families of firefighters stricken with cancer. He said the department had recognized for a long time cancer's impact on the force, and said the administration of Mayor Martin J. Walsh is supporting resources that address firefighters' health and safety.
Finn showed families four versions of the video — one lasting seven minutes; the others much shorter — saying he wanted them to have a first look at the project before making it public. The department plans to show the video at the city's 33 firehouses, and to the mayor and City Council. The video also will be on the department's website and, later, on social media. Finn will also present the video at a meeting on firefighter cancer prevention in Phoenix this week.
The department used $30,000 from a training grant to have the video made.
The video uses somber music that builds, aiming to tug at the heartstrings and conscience of a force known for its toughness and machismo. Tearful participants urge firefighters to always use their air tanks and wash their soot-laced clothing after a blaze.
At the end of the video, a roster of the lives lost to cancer rolls on the screen.
"You want to make it memorable,'' said Steve MacDonald, spokesman for the department. "Firefighters go through a lot of training. The purpose of the video is to make an impression in the firefighters, to make them remember it."
The video starts with Firefighter Kevin McNiff, a 27-year member of the force, sitting in front of a wall of portraits posted on the third floor at Boston Fire Department headquarters. He suffers from stage four kidney cancer that has spread to his lungs.
"Cancer is taking the job I love away from me,'' he says.
Matthews was diagnosed with pancreatic cancer on Mother's Day last year, he said in an interview. He had surgery in the fall to remove 40 percent of his pancreas. But the cancer raged back and has metastasized to his liver. Doctors have given him nine months to live, he said.
He does not know what caused it, but can't help but wonder whether the hazardous fumes and chemicals he encountered while extinguishing fires over the past 30 years had something to do with it.
"The new kids come on, and they think they can lift the whole world; you are not thinking that'' you can get cancer, Matthews said in the interview.
He said he knows many other firefighters with the disease. He named 10 people he said have had cancer during his years in the firehouse on Columbus Avenue.
"I call it the contaminated house,'' said Matthews, who eventually moved to another station.
He worked as an engineman, among the first firefighters charging into a building to the seat of a blaze, where the fire rages most ferociously. After firefighters would tamp down the fire, Matthews said he did not always keep on his air mask, a bad habit he hopes other firefighters avoid.
"For the younger guys, wear your mask all the time,'' Matthews warned. "Old-school guys like me didn't always keep our masks on. Guys, we aren't made out of plastic."
The video also features Billy Foley, a 64-year-old retired member of the force who has brain cancer and stage four lung cancer. A 38-year veteran of the department, Foley says in the video he and his colleagues never talked about cancer in the firehouse and that maybe he did not wear his air mask when he should have.
In an interview, Foley said he "was not one of those people who went to a hospital — or a doctor." But in October 2009, while battling a fire on Purchase Street, he was taken to the hospital when the hatchback of his chief's car struck him on the head. His vision instantly became blurry.
Less than a week later, he said doctors operated on his head and removed a tumor the size of a tennis ball. The cancer had originated in his lungs, he said in an interview.
His life is now laced with regular cancer treatments and visits with specialists.
At the screening Thursday, Foley sat with his wife and five children. An image of him came on a large screen. His children leaned into each other as he spoke. His wife, Maryann, wiped tears from her eyes.
"It affects our family tremendously,'' she later said. "It's life-changing."
Meghan E. Irons can be reached at email@example.com. Follow her on Twitter @meghanirons.