TRELLEBORG, Sweden — On a recent September afternoon, the director Tobias Lindholm sat with Ingrid and Joachim Wall on the couple’s terrace overlooking the Baltic Sea and watched as the Walls’ dog, Iso, edged his nose toward a plate of raspberry cake.
“Iso is the star of the show,” Mr. Lindholm joked. Given the horrific events that brought the director and the couple together, this lighthearted tone might seem surprising. But the joke — and the laughter it elicited on the terrace — reflected some important truths about the television series on which the three have collaborated.
That series, “The Investigation,” which premieres in Denmark and Sweden on Sept. 28 and will screen in Britain on the BBC later this year, focuses on the investigation into the murder of the Walls’ daughter, the Swedish journalist Kim Wall. Iso does indeed play himself in the series. The “starring” role is indicative both of the fictionalized production’s fidelity to the truth and of its larger project: to focus on the human goodness in a case seemingly defined by its depravity. “The Investigation” may have been shot near the crossing between Denmark and Sweden that gave “The Bridge” its title, but its message inverts the despair typical of Nordic noir television.
In August 2017, Ms. Wall, 30, was on assignment for the magazine Wired when she boarded a homemade submarine to interview its Danish inventor, Peter Madsen. When she did not return home, the police began searching for the craft in the Oresund, the stretch of water that separates Denmark and Sweden. Mr. Madsen eventually reappeared, initially claiming that he had brought Ms. Wall safely ashore before the submarine sank. But he changed that story when the vessel was recovered and, after her torso was discovered on a beach in Copenhagen, he later admitted to dismembering Ms. Wall’s body. In April 2019, Mr. Madsen was convicted of sexually assaulting and killing her, and was sentenced to life in prison.
The brutality of the crime, as well as the eccentricity of its perpetrator, made it one of the most closely watched cases in Scandinavian history. An Australian documentary called “Into the Deep,” which focuses on Mr. Madsen and the people who worked with him, was acquired by Netflix but later pulled from its lineup. This month, Discovery Networks Denmark began airing a documentary series based on secretly recorded telephone interviews with Mr. Madsen in prison.
“The Investigation,” produced by Miso Film, a Scandinavian company, does not depict the crime or its perpetrator — in fact, Mr. Madsen’s name is never uttered. Instead, Mr. Lindholm chose to focus his six episodes on the detectives, divers and scientists who gathered the evidence that would convict him.
“I wanted to make a story about heroes, so I didn’t have room for him,” said Mr. Lindholm, who also directed the Oscar-nominated film “A War.”
“It liberated me to tell a humane story,” he added.
The genre of Nordic noir has exploded in literature and onscreen over the past decade, and is usually characterized by a horrific crime, a gloomy setting and protagonists tormented by personal demons. Although Mr. Lindholm had experience with shows that probe human darkness — he directed two episodes of “Mindhunter,” the American series following the F.B.I.’s early efforts to psychologically profile serial killers — he said that he wanted something different for “The Investigation.” A meeting with Jens Moller, the pragmatic, good-natured Danish homicide chief who led the investigation into Ms. Wall’s killing, persuaded him to focus the show on someone who was simply good at his job.
“The story he told me about the case was very different from the dark, horrifying story that I saw in the press,” Mr. Lindholm recalled. “He told me a story about police officers who did their job and about divers who spent months in the dark, cold water trying to find what they could so that parents could bury their daughter.”
As played by Soren Malling (who also starred in “The Killing,” which helped to popularize the Nordic noir TV genre abroad), Mr. Moller is reserved but not tormented, and he doesn’t so much crack the case as doggedly compile the evidence that allows it to be successfully prosecuted. “He became my hero,” Mr. Malling said of the homicide chief. “This is a guy who never appeared on the cover of a magazine. He just worked as a policeman for 40 years.”
Mr. Moller introduced Mr. Lindholm to Kim Wall’s parents, who had come to think of the officer as a friend. Although the couple had turned down most media requests, they decided to work on the show in part because of the director’s decision not to include Mr. Madsen. “We don’t want to make a commercial for this guy,” Mr. Wall said. “He’s already cost us so much.”
But they were even more persuaded by what Mr. Lindholm did want to focus on. “We see this as a tribute to the ordinary people — the normal policeman, the normal diver,” Ingrid Wall explained. “Not just because they were doing their jobs, but because they did their jobs with determination. They were out there, on the Oresund in November, with big waves, and freezing cold.”
In some ways, the show’s focus echoed their daughter’s work as a journalist, which appeared in many publications, including The New York Times. She wrote about women fighting for the Tamil Tigers and about Ugandans tortured under Idi Amin. “Kim wanted to give a voice to people who didn’t have one,” her father said. “She was always looking for the story behind the story.”
By the time Mr. Lindholm met the Walls, they were working on a book about their daughter’s life and had started the Kim Wall Memorial Fund, which awards grants to young female journalists. And they had also, somehow, figured out a way to embrace life. “Even if it’s the absolute darkest time, there is light on the other side,” Ingrid Wall said. “So, even if we have been hit by this tragedy, we can still laugh, we can still enjoy walking the dog on the beach.”
The couple did not have veto power over the script, but they did advise Mr. Lindholm on a few places where moments didn’t ring true. In an early draft, for example, the director figured that, as reserved Scandinavians, the Walls’ neighbors would back away from the grieving couple. But the couple experienced just the opposite, and the corrected scene, in which their neighbors bring them flowers and condolences, is one of the most moving in the series.
Mr. Wall is portrayed in the show by Rolf Lassgard, and Ingrid Wall by Pernilla August, who has appeared in two “Star Wars” movies. “To be played by Luke Skywalker’s mother,” Ms. Wall said, “is pretty great.” The Walls figure in the series not just as survivors of tragedy, but as active participants in the quest to find meaning in it. In one episode, Mr. Wall initiates an important plot turn when he suggests that the police use “cadaver dogs” capable of locating scents originating underwater.
Those small moments may not have the same dramatic force as the complicated twists of the average Scandinavian crime drama. But they add up to something affecting in its own right: a portrait of a society in which, even in the face of horrific violence, things work as they should.
Pausing by the heart-shaped memorial to Kim Wall that anonymous well-wishers have created on the beach near the Walls’ home, Mr. Lindholm reached down to pet Iso. “Systems that work, human beings who believe in society,” he said. “That’s a Nordic story, too.”