CHAPTER SIX
The forensics team had cordoned off a section of ice roughly fifty yards from where Sarah Quinn's body had been extracted, their equipment creating an incongruous high-tech tableau against the primitive backdrop of frozen lake.
Isla approached the lead technician, a thin woman named Carol Stevens who she'd worked with on two previous cases.
"What have you got, Carol?"
"Entry point's over here," Stevens replied, leading them to a roughly circular hole in the ice, perhaps three feet in diameter.
The edges were already beginning to refreeze in the bitter morning air, but the opening was still clearly visible.
"Based on the body's position when recovered and the current patterns, this is definitely where she went through. "
Isla knelt beside the hole, studying the formation of the ice around its perimeter. Even to her untrained eye, something looked wrong. The edges were too smooth, too uniform for a natural break.
"Sullivan," she called, gesturing for her partner to join her. "What do you think?"
Sullivan approached and crouched beside the opening, his experienced eye taking in details that would have escaped most observers. As a lifelong resident of Duluth, he'd seen countless ice conditions, understood the difference between natural formations and artificial alterations.
"Son of a bitch," he muttered after a long moment of examination.
"What?"
"Look at the edge pattern here," he said, pointing to a section where the ice curved inward in an almost perfect arc. "See how clean that line is? Natural ice breaks are jagged, irregular. This looks like it was cut."
Stevens nodded, her expression grim. "That's what we're thinking, too. We found what appear to be tool marks along the perimeter—very fine cuts, made with something sharp enough to slice through eight-inch ice without creating the fracture patterns you'd see from impact."
Isla felt her pulse accelerate. "A saw?"
"Most likely. Something with a very fine blade—probably a wire saw or a specialized ice cutting tool. Someone who knew what they were doing could weaken this section enough that it would give way under even minimal weight, but still look solid from the surface."
The implications hit Isla like a physical blow. Not an accident. Not even a case of someone taking foolish risks on unstable ice. This was murder, planned and executed with the kind of technical knowledge that suggested experience.
"How long would it have taken?" Sullivan asked.
"To make cuts like this? Maybe twenty, thirty minutes if they knew what they were doing. Could have been done the night before—the ice would refreeze enough to hide the worst of the tool marks, but still be fatally compromised."
Isla stood slowly, her mind already connecting this evidence to the case that had brought her to the lake in the first place.
Alex Novak, found dead in an ice fishing hole with suspicious circumstances.
Sarah Quinn, killed by artificially weakened ice designed to look like a tragic accident.
The pattern she'd been tracking for months was becoming impossible to ignore.
"This isn't random," she said to Sullivan as they walked back toward their car. "Someone's using the lake as a weapon, making murders look like accidents."
"You think this is connected to the shipyard case?"
"I think we're looking at the same killer." The certainty in her voice surprised her, but the conviction felt solid. "Someone who understands ice conditions, who knows how to manipulate them, who can plan these attacks weeks in advance."
The drive back to the FBI field office took them through downtown Duluth, past the frozen harbor where massive freighters sat locked in ice like prehistoric beasts.
Isla stared out at the scene, seeing it now not as a winter wonderland but as a hunting ground.
Somewhere in this community, someone was using the lake's deadly reputation to hide multiple murders.
By the time they reached the federal building, she'd made her decision. It was time to get Kate's authorization to officially pursue Sarah Quinn's death as part of her ongoing investigation.
Kate's office occupied a corner of the third floor, its windows offering a commanding view of the harbor and the lake beyond.
When Isla and Sullivan entered, they found her reviewing case files with the methodical attention that had made her reputation as one of the Bureau's most effective managers.
"Sarah Quinn," Isla began without preamble. "The environmental scientist who went through the ice this morning. Forensics confirms artificial manipulation—wire saw cuts, deliberate weakening. It's the same methodology I've been tracking."
Kate set down the file she'd been reading and fixed Isla with her full attention.
The SAC had been briefed on Isla's theory about connected homicides months ago, had authorized preliminary investigation while remaining cautious about committing full resources to what might be pattern recognition rather than actual serial activity.
"You're certain it's connected to your other cases?" Kate asked.
"The MO is similar to some of the deaths—artificially weakened ice designed to cause failure under normal loading conditions. Technical sophistication that suggests experience and planning. Some of the deaths I suspect are linked are indistinguishable from accidents—some might even have been actual accidents, but this one was no accident. That much is certain.”
Kate was quiet for a long moment, her fingers steepled as she processed the information. Through the office windows, snow continued to fall, adding another layer to the white landscape that had become the backdrop for multiple murders.
"The boot print from the Novak scene," Kate said, her memory for case details as sharp as ever. "Any connection to Quinn?"
"Different location, but same general methodology. Someone who understands Lake Superior's winter conditions and knows how to exploit them." Isla paused, meeting Kate's gaze directly. "I need authorization to treat Quinn's murder as part of the serial investigation. Full resources, expanded scope."
"You've been building this case for some time," Kate observed, her tone neutral but her eyes sharp with assessment. "Some might say you're too invested to see it objectively."
The criticism stung because it echoed Isla's own doubts—Miami had taught her the dangers of trusting theories over evidence, of letting personal investment override analytical judgment.
But the forensics from Sarah Quinn's scene weren't theoretical.
They were concrete proof that someone was deliberately killing people and making it look like accidents.
"I am invested," Isla admitted. "But the evidence speaks for itself.
Artificially weakened ice, victims with connections to the port community, a timeline that suggests patience and methodical planning.
Either we have a serial killer who's been operating successfully for years, or we have the most unlikely series of coincidental murders in Bureau history. "
Sullivan, who'd remained quiet during the exchange, spoke up. "Kate, I've reviewed Isla's work on this. The connections are solid. And now with Quinn's death showing identical methodology, we'd be negligent not to pursue it as a connected series."
Kate studied them both for another long moment, her expression revealing nothing of the calculations happening behind her eyes. Then she nodded, the movement decisive and final.
"Full investigative resources," she said, her voice carrying the authority that had made her a natural leader.
"You'll have access to additional cold case files, expanded team if you need it, and authorization to treat these as connected homicides.
But I want regular briefings, and I want you to keep the local PD fully informed.
The last thing we need is a jurisdictional dispute while there's a serial killer operating. "
"Understood," Isla replied, feeling the satisfaction of validation mixed with the weight of responsibility. Kate's authorization transformed her year-long suspicion into official Bureau investigation, but it also meant that failure would be more public and more consequential than before.
"One more thing," Kate added as they prepared to leave.
"I'm trusting your instincts on this, Isla.
I know Miami shook your confidence, but you're a good investigator.
Don't second-guess yourself into paralysis, but don't let theory override evidence either.
Follow where the facts lead, even if it's somewhere you didn't expect. "
The advice was exactly what Isla needed to hear—permission to trust her analytical abilities while remaining open to possibilities that might challenge her assumptions.
Kate understood the balance between confidence and humility that effective investigation required, and she was giving Isla room to find that balance on her own terms.
As they left Kate's office and headed back toward their desks, Isla felt the familiar excitement of a case finally breaking open after months of patient development. Sarah Quinn's murder had provided the concrete evidence that transformed theory into action, suspicion into investigation.
Somewhere in Duluth's frozen landscape, a killer was going about his routine, confident that his crimes would continue to be mistaken for accidents. But that confidence was about to be challenged by the full weight of federal investigative resources.
The hunt had officially begun.