Pleading, scared and at times nearly out of breath, a Wren High School football player begs an Anderson County 911 dispatcher to send help for his friend, 17-year-old Brandon Tyson, as heard in the call.

It's about 2 a.m. on Saturday, Sept. 8, 2018, and at the home of Mark and Nikki Chastain in Piedmont, things are going horribly wrong.

The teen caller tells the dispatcher that Tyson, whom he calls Brad, has ingested something and is "acting crazy."

"He took something, and he's out of control," the caller says. "He bit my friend's dad's face, and he's beating everybody up. Please hurry up. Please!"

The dispatcher asks the caller what Tyson took, and twice the teen says he doesn't know.

"We have no idea," the teen caller says. "He said he took mushrooms, but then he's going crazy."

"So he took mushrooms?" the dispatcher repeats.

"Yes sir, that's what he said," the teen answers. "But there's no way. He's so crazy."

The dispatcher asks if everyone there ingested mushrooms.

"No, I haven't done anything," the teen answers. "I just played a football game, and I really don't want to get a reputation, sir... Please, sir, I'm scared... Can you please get here? Please, now!"

The teen caller tells the dispatcher that Tyson has no stick or weapon but that the homeowner, Mark Chastain, may have a gun in the house.

"Mark, it's me; please don't shoot me," the teen is heard saying in his call.

Before the 10-minute 911 call is over, the sound of gunfire is heard in the background, including the shot that cost Tyson, a Wren High School senior, his life.

No charges have been filed in Tyson's death.

Investigators at the Anderson County Sheriff's Office and David Wagner, the 10th Judicial Circuit solicitor, said the facts of the case show that Chastain acted in self-defense when he shot Tyson.

The Sheriff's Office released the investigative file about Tyson's death, including a recording of the 911 call, to the Independent Mail and The Greenville News in response to a Freedom of Information Act request.

Reached by phone, Chastain declined to comment on what happened.

"My attorney has advised me not to say anything," he said. "I wish I could. There's a lot of wrong information out there. I've just been told not to say anything. It was just a bad situation, and I wish I could say more."

The Independent Mail and The News also reached out to the teen 911 caller by contacting his mother, Robin Williams. The teen did not respond to a request for comment, but his mother said her son had tried to help Tyson, who was at the Chastain home with several other teenage boys.

"I hate that this whole thing happened," Williams said. "It's awful. But some people are trying to make our children out to be monsters or make Mark out to be a monster. They aren't."

Toxicology tests conducted after Tyson's death show that he tested positive for marijuana and for a compound in hallucinogenic mushrooms. Chastain tested positive for marijuana and had a blood-alcohol content of .074, according to records. A person with a .08 blood-alcohol content is legally considered impaired in South Carolina.

Tyson's parents, Jeremy and Nikki Tyson, are hopeful that another investigative agency will review the case. They have questions about whether the Sheriff's Office properly collected and reviewed all evidence. Anderson County Sheriff Chad McBride and his investigators say they looked at the case thoroughly."

The Tysons filed a wrongful-death lawsuit against Chastain, and Chastain filed a counterclaim. That suit has been settled with terms that have not been disclosed.

Now, the Tysons have only questions — and memories of the boy they lost.

He wanted to be an underwater welder. His expectation of what that would cost, his projected salary after college and his equipment estimates are handwritten on a notebook that still rests on the desk in his bedroom.

"There are so many things we still don't understand about what happened," Nikki Tyson said. "I would say to parents: 'You really have to know and understand who your child is with, even if it's an adult.'"

Follow Nikie Mayo on Twitter @NikieMayo or email her at mayon@independentmail.com.

More:A teen ate mushrooms and went 'wild,' friends said. Soon he was shot by a friend's father