The victim, Stephanie DeJesus, 38, had driven to the Gordon Avenue home where Justin Fisher and Joelle Martucci lived with their young son the night of Feb. 23, documents say security video shows.
She'd driven there from a nearby pharmacy, according to an affidavit filed in Superior Court in Paterson.
Martucci, 24, pulled up afterward in a white SUV, it says.
Both vehicles eventually left nearly an hour and a half later, the affidavit says, without identifying either driver.
DeJesus, who had a son herself, was born and raised in Paterson, lived in the city all of her life and worked as a cardiovascular technician for St. Michael's Hospital in Newark.
Roughly 36 hours after the vehicles left Gordon Avenue, a caller told Paterson police on Friday morning that there was blood dripping from the trunk of what turned out to be DeJesus's car off the corner of James Street and Ryerson Avenue.
DeJesus had been beaten to death, authorities said following an autopsy.
Detectives arrested Martucci on Monday, Feb. 28, during warranted searches of the couple's home, her previous address on Coolidge Street and the SUV.
Questioned by detectives, Martucci said she'd come home the night of the killing to find a "large box/bag" in the living room. She said she also noticed "a portion of the floor/flooring in the living room area [had been] ripped up.”
She then told them she saw Fisher, 29, and his dad, Ali Gibson, 51, carry the large container to DeJesus's car, the affidavit says.
Detectives instantly obtained warrants for the arrests of Fisher -- who also has a son with another woman -- and Gibson. Both surrendered to the Passaic County Sheriff's Office on Wednesday, March 2, authorities said.
All three defendants remained held in the Passaic County Jail on murder and conspiracy charges pending first appearances in Central Judicial Processing Court in Paterson.
Meanwhile, questions remain.
These include suspected motive, as well as what specifically caused the blunt-force trauma that a medical examiner said killed DeJesus.
Also unanswered at this point is what role was played in the case by the U.S. Secret Service, which was among the agencies thanked by Passaic County Prosecutor Camelia Valdes in a joint news release with the Paterson and Totowa police chiefs announcing the arrests.
CHECK BACK FOR MORE DETAILS
Click here to follow Daily Voice Franklin Township and receive free news updates.