An Indiana woman is behind bars facing a slew of felony charges after an alleged threesome set up on a dating app turned into the horrific rape and murder of her two victims, one of whom was declared “deceased and beyond help” after being brutally beaten to death.

The suspect, Heidi Kathleen Carter, 36, has been charged with murder, two counts of intimidation with a weapon, rape, two counts of felony criminal confinement, assisting a criminal, carrying a handgun without a license, and abuse of a corpse, 14 News reported.

Police said a woman approached authorities late Tuesday night after she stumbled upon a dead body inside Carter's home at 1801 Stinson Avenue, where she was called to help clean ahead of an inspection. 

The witness said she took a seat on a pile of blankets for a quick break but later realized “that under the blankets was a dead body,” an arrest affidavit detailed. Her grim discovery saw the woman scrambling to escape the home and immediately alerted authorities about it.

Responding officers from Indiana Police and the Evansville Police Department were deployed to the home at around 11 p.m., believing they were dealing with a “possible kidnapping and murder," the Daily Beast noted.

To their surprise, they were met by a gun-wielding Carter outside the home who told the cops there were still “several people '' inside the home. Police would then surround the area and begin instructing those inside to come out and surrender.

One unidentified man would immediately comply with police orders and was released. However, a second man, later identified as Carter's boyfriend Carey Hammond, would aggressively rush out of the front door to attack police with an object in his hands. 

He was then fatally shot by several officers in what “appears to be a suicide by cop situation," Evansville Police Department spokeswoman Sergeant Anna Gray said. 

When police entered the home, they found a woman who was tied up, shackled, and had visible injuries all over her body. 

“Another individual was located inside the residence but unfortunately was deceased and beyond help. The manner of death appeared suspicious and gruesome. He had been restrained, duct-taped, beaten, and strangled,” Gray noted. 

Minutes later, police found two teenagers upstairs and safely evacuated the minors, which “took officers by surprise."

According to a police affidavit, Carter found the woman victim on a “lesbian dating app" and would later invite the new connection and her boyfriend for a threesome at her Stinson Avenue earlier that day.

Investigations unraveled that Hammond, who was shot at the scene, arrived home during the trio's sexual activity, sending him into a jealousy-fuelled rage, according to Law & Crime.

The man allegedly ruthlessly pummeled the guests with a baseball bat before ordering Carter to help him chain them up.

“They also tied and shackled the female victim while the male suspect raped her multiple times throughout the day, from Oct. 19 to Oct. 20,” Gray said.

Following her arrest, Carter has been booked into the Vanderburgh County jail and told police she had decided to go along with Hammond's order to restrain the victims out of fear he might harm or kill her. 

Police further noted that the deceased male suspect carried a history of criminal offenses. 

Heidi Kathleen Carter Heidi Kathleen Carter, 36, has been charged with murder, two counts of intimidation with a weapon, rape, two counts of felony criminal confinement, assisting a criminal, carrying a handgun without a license, and abuse of a corpse. Vanderburgh County Sheriff's Office