An Iowa resident confessed to fatally stabbing his wife in January, revealing he had meticulously plotted the murder just hours before carrying it out.

James Martin, aged 47, claimed his motive was to relieve Amber Martin from “misery,” as he perceived their financial situation to be hopeless, according to a report from KCRG.

During the incident on January 16, Martin’s mother was present in the home and pleaded with her son to cease, even attempting to intervene by placing herself between him and Amber, as detailed in newly unveiled court documents.

Authorities responded to an emergency call at the Coralville residence shortly after 6:30 a.m., discovering Amber Martin with multiple knife wounds. Despite efforts to save her, she was declared deceased on the scene.

In their investigation, police discovered a bloodied knife in the kitchen sink, along with blood traces and stained clothing throughout the area.

James Martin’s mother recounted to officials that she had arrived at the home around 1 a.m. due to worries about her son’s mental wellbeing. She mentioned that she dozed off on the living room sofa, awakening to a disturbance she initially attributed to the cat, until she heard Amber Martin’s cries for help.

She said she saw her son stabbing his wife and rushed in to try to stop him.

Investigators said in the newly released affidavit that Martin planned the murder and ambushed his wife, Law&Crime reported.

“In the hours leading up to the defendant killing the victim, the defendant formulated a plan to kill the victim,” the complaint said. “The defendant retrieved a kitchen knife and surprised the victim as she exited another room and stabbed the victim repeatedly.”

Amber Martin was a medical laboratory scientist supervisor in the University of Iowa Health Care system, Muddy River News reported.

James Martin was arrested and charged with first degree murder, KCRG reported.