In the video saved to Nicholas Forman’s phone, Sabrina Harooni lies motionless on a lawn in Montgomery County. A voice from behind the camera taunts her.

“This is what cheating liars get,” says a man police believe to be Forman, 23, the woman’s boyfriend. “You hear me?”

On Monday, police say, Forman buckled Harooni’s battered body into an Uber and had the driver take them to a hospital. He told the driver and, later, nurses at Pottstown Memorial Hospital that Harooni, 22, had been attacked by a group of women the night before.

Authorities say that was a calculated lie. The real assailant, they allege in documents filed late Thursday, was Forman.

Forman, of Perkiomen Township, was arrested at his home Thursday afternoon and charged with first- and third-degree murder, according to court records. There was no indication he had hired an attorney.

Emergency room doctors who examined Harooni’s body called state police to report that she had been assaulted. She had evidence of severe head trauma, according to the affidavit of probable cause for Forman’s arrest.

When Forman dropped Harooni’s body off at the hospital, it was “ice cold,” the hospital staff told police. There were bruises to the neck and dried blood in the nose. Forman calmly told the medics that she had been in that condition “for a while,” according to the affidavit.

During an interview with state troopers, Forman said he and Harooni had gone to a bar in Oaks to watch the Super Bowl. There, he said, Harooni, his girlfriend of seven months, got into an argument with three women and gave them his address in case they wanted to meet her there later to fight, the affidavit said.

Forman told investigators that’s just what happened. He didn’t get involved, he told police, because he’s on probation in Philadelphia. (Court records show that he pleaded guilty to driving under the influence and resisting arrest in 2017.)

He said Harooni was badly injured in the fight, but seemed fine until the next morning, when he decided to take her to the hospital, according to the affidavit.

An Uber driver who drove the couple home from the bar in Oaks gave a different account. He said the couple got into a heated dispute after Harooni mentioned getting a text message from an ex-boyfriend, according to the affidavit. Forman became irate and demanded to see her phone, and Harooni said he was scaring her, the driver told investigators.

When he pulled away, the driver said, the two were arguing in the street, and Forman was refusing to allow her into the home. Hours later, investigators say, she was dead.