The Tennessee man who killed his estranged wife and their grandchildren masqueraded in a “Friday the 13th” mask and posted about his break-up woes before his murder-suicide rampage.

Gary Barnett, 48, posted a grim quote just days before he shot and killed his wife Regina, her daughter Brittnee Perez and her two kids at his home in Marion County around 9 pm. Thursday.

A third child also was killed in the bloodbath and another unnamed adult suffered injuries from gunshot wounds but is alive in hospital, according to Marion County Sheriff Bo Burnett.

In a TikTok video re-posted by Barnett to his Facebook page on June 11, a woman says: “One really messed up things that guys experience after a breakup is when their ex not only pretends, but spreads word that he is a bad man just so she doesn’t feel guilty over how she treated him.”

A month earlier, his estranged wife Regina Barnett claimed her husband had “50 to 60 guns in his room” and that she was “afraid he will get drunk and shoot me,” in a request for a restraining order against Gary, which was approved by a judge.

In another bizarre social media post months before the deadly shooting, Barnett is seen wearing the Jason Voorhees mask from the “Friday the 13th,” horror film franchise, in which the masked killer terrorizes people by stabbing them to death with a huge knife.

Just four days ago, Barnett also posted a quote from Marvin Heemeyer, a notorious Granby, Colorado, man who felt he had been wronged by his town. Heemeyer bought and foritfied a bulldozer in 2004 which he sealed himself inside with cement and set about destroying the town.

After destroying the town hall, the house of a ex-mayor and various other buildings, as authorities boxed him in, Heemeyer shot himself.

Heavy machinery worker Barnett posted on his Facebook timeline an infamous quote from Heemeyer: “I was always willing to be reasonable until I had to be unreasonable. Sometimes reasonable men must do unreasonable things.”

Barnetts social media was scrubbed of any evidence of Regina, but still included pictures of his children and dogs, amongst a Peanuts cartoon which has been changed to read “tell me what love is Chuck,” whith him replying: “The feel of recoil and the smell of gunpowder.”

In her restraining order, Regina said she was afraid her husband not only threatened to shoot her but her dog.

Deputies initially responded to a shots fired call Thursday night, but found the Barnetts’ home fully-engulfed in flames.

The Tennessee Bureau of Investigation is heading up the case.

“It’s a domestic situation, evidently that has been ongoing for a pretty good while,” Sheriff Burnett said to WTVC NewsChannel 9.