Colorado woman's stalker turns out to be husband in shocking murder case
In a chilling case of deception and domestic violence, what appeared to be months of stalking by an ex-boyfriend turned out to be an elaborate scheme orchestrated by a Colorado woman's own husband, culminating in her murder just days before Christmas.
Kristil Krug, a 44-year-old chemical engineer and mother of three from Broomfield, was discovered dead in her garage by an officer on Dec. 14, 2023, after responding to a welfare check requested by her husband Daniel Krug.
According to police recordings, Daniel called the non-emergency line saying, "I don't think this is an emergency, but this feels really weird... my wife isn't responding to text messages or phone calls."
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In his police interview, Daniel told detectives that his marriage had been deteriorating, admitting they were sleeping in separate bedrooms and claiming that he had asked for a divorce.
"Daniel Krug was losing control and his marriage was falling apart. Kristil wanted out, but Daniel Krug was in denial," Deputy District Attorney Kate Armstrong told jurors during the trial.
Investigators would soon discover a disturbing truth that Daniel had been impersonating a boyfriend Kristil had as a teenager for months, terrorizing his own family before ultimately killing his wife.
The case, which initially appeared to be the tragic end to a stalking situation, revealed how Daniel thoroughly created a false narrative using burner phones and carefully planned digital deception, all while playing the role of a concerned husband.
"He decided he was going to play puppet master by impersonating Jack Anthony Holland, stalking and terrorizing his family for months before murdering Kristil, 11 days before Christmas," Armstrong told jurors.
In the months leading up to her death, Kristil had become increasingly concerned about emails and texts she was receiving from someone claiming to be Holland, her ex-boyfriend from more than 20 years ago.
The messages escalated from attempted reconnection to threats against both Kristil and Daniel. In October 2023, Kristil went to police with a detailed spreadsheet documenting every interaction with her apparent stalker. Police body camera footage showed Kristil expressing her fears.
"This is exhausting," she told officers. "It has definitely made me paranoid everywhere I go."
The murder investigation took a turn when detectives discovered some of the threatening messages originated from IP addresses at Daniel's workplace, the Colorado Department of Public Health and Environment.
Further digital forensics revealed Daniel used burner phones to create the illusion of a stalker, even photographing himself to send threatening messages about the fictitious stalker "watching" him.
Detectives determined that Holland never stalked Kristil and verified his whereabouts in a different state at the time she was killed. He was fully cleared by authorities.
On the morning of Kristil's murder, police believe Daniel attacked her shortly after she returned from dropping off their children at school. He allegedly struck her in the head before stabbing her in the heart.
Police said that, in a calculated move to establish an alibi, he used her phone to schedule text messages to himself and others, disabled home security cameras and placed blue tape over their Ring doorbell camera.
The case against Daniel was strengthened when investigators uncovered disturbing internet searches he had made the night before the murder, including "how much head trauma do you need to cause to knock someone unconscious?"
A former girlfriend of Daniel's testified during his trial that he had allegedly stalked her in a similar manner decades earlier, creating multiple fake online personas to harass her after their breakup -- a pattern that authorities said eerily matched the tactics used against Kristil. Daniel was never charged with any crime regarding the allegations made by his former girlfriend.
In April 2025, a jury found Daniel guilty of first-degree murder, stalking and criminal impersonation after he pleaded not guilty. He was sentenced to life in prison without the possibility of parole. In a statement to "20/20," Daniel wrote that he "maintains his innocence and will fight this wrongful conviction on appeal."
"Every day is a difficult day," Linda Grimsrud, Kristil's mother, told "20/20." "You wake up and you feel the pain, and then you just try to go on with your day."
