A Duluth man was robbed at knifepoint and assaulted after hiring a woman from Craigslist to pose for photos in his Lakeside home, according to criminal charges filed last week.

The 48-year-old Lakeside man told police that the woman, Katie Joann Schultz, had agreed to pose for a photo shoot in front of the model racetrack he had built in his basement.

But when Schultz showed up to his house on Saturday, July 18, the robbery plot was quickly revealed. Schultz's boyfriend, Robert Daniel Laurent Derrick Robinson, entered the residence brandishing a butcher knife and proceeded to take the man's wallet and the contents of a safe, according to court documents.

The homeowner, meanwhile, suffered two fractures to his orbital socket - injuries that authorities said may require surgery.

Robinson, 22, was charged Friday in State District Court in Duluth with aggravated first-degree robbery, a crime that carries a maximum of 20 years in prison. Schultz, 22, was charged earlier in the week with aiding and abetting the crime.

Both are being held at the St. Louis County Jail on significant bail amounts.

According to the criminal complaints:

The victim began communicating with Schultz on Craigslist before the incident. They arranged for Schultz to come to his home on July 18, but she kept changing the plan throughout the day.

Schultz finally arrived at the residence, on the 4800 block of Cooke Street, at about 9 p.m. She was alone and said she was hungry, so the man ordered a pizza.

The victim excused himself to use the restroom and came back to find Schultz's boyfriend, Robinson, coming at him with a butcher knife. The man told police that Robinson put the knife to his throat, threatening to kill him, and ordered him to take him to the safe in his bedroom.

Robinson attempted to tie him down with an extension cord but failed. The victim attempted to run, but Robinson pushed him into the wall and began punching him.

The victim reported that he was finally able to escape by kicking the suspect in the groin. Robinson and Schultz fled the residence with several objects, including $80 from the man's wallet, a large silver collection and several family heirlooms.

Officers arrived at the scene at 9:46 p.m., just minutes after a 911 caller reported hearing a male calling for help. Eyewitnesses reported seeing a black male carrying a purse, accompanied by a white female.

The bloodied victim was found on the ground outside the house and was taken to St. Luke's hospital emergency room for treatment.

Schultz was arrested near the scene. Police said she was carrying a laptop computer that was stolen from the victim's home. Robinson was arrested four days later at a residence on the 300 block of East Superior Street.

Police said Schultz gave an interview, admitting that she had called in a "third party" to assault the homeowner. Robinson also sent a text message to Schultz's mother, indicating that it was his fault she was in jail.

Larson's mother told police that her daughter had known Robinson since elementary school and that they were in an "on again, off again" for about three years.

Robinson has a substantial criminal history, including two felony convictions for second-degree burglary, and has been accused of four other serious crimes this year alone.

"This young man's continued dangerous behavior makes me believe he needs to be in jail," Duluth Police Chief Gordon Ramsay wrote in a Facebook post Monday.

In addition to the most recent charges, Robinson is accused of aggravated first-degree robbery after allegedly robbing a man at gunpoint in Duluth in May. He's also facing a firearm charge in Pine County, and in Itasca County he's charged with drug possession and escape from custody.

Assistant St. Louis County Attorney Kristen Swanson requested that bail be set at $125,000. Judge Sally Tarnowski agreed.

"(Robinson) has quickly amassed four separate violent felony level criminal files since being discharged from probation in January of 2015," Swanson wrote in a bail recommendation. "The State has grave concern for public safety considering the nature of the allegations in the two St. Louis County files, which demonstrate (his) volatility and increasing propensity for violence."

Swanson noted that Schultz's history was minimal - with only a shoplifting conviction on her record - but argued that the allegations demonstrate that she is a dangerous person who is "willing to resort to vigilante type justice."

Tarnowski set Schultz's bail at $25,000.

Both defendants are due back in court on Aug. 12.