Warning: This story contains graphic content.

Joshua Frank hunched over and sobbed in the corner of an RCMP interrogation room as he claimed he was both a killer and a victim.

The 32-year-old confessed he shot Gordon, Sandra and Monica Klaus on Dec. 8, 2013. But he told investigators Jason Klaus had a gun pointed at him the whole time and forced him to do it.

"He just stood there and told me what to do," Frank said through his tears. "I was in front. And he told me shoot them or you're getting shot.

"I wish I would have turned around and shot him."

The confession came at 10 p.m. on Aug. 16, 2014, after a long day of relentless questioning by Staff Sgt. Josh Graham and Cpl. Joany Paradis.

Frank told the Mounties he had been groomed and sexually abused by Klaus for three years and that the abuse began when he was 14 years old.

The revelation followed a question. "I'm wondering, has he ever sexually abused you?" Paradis asked.

"I'm not gay," Frank responded. 

"People understand predators that feed on kids by feeding them drugs and taking advantage of them, Josh," Graham responded.

"Yeah, that happened a couple of times," Frank admitted. "I've never told anybody that before.

"Nobody knows and I really don't want people to know either."

It was a surreal scene that played out in the Red Deer courtroom as the two accused killers watched the taped interrogation recorded three years ago.

In one corner, Klaus had a smirk on his face. At the other end of the long box, Frank blinked furiously, then leaned against the wall and began to cry.

Justice Eric Macklin had to remind the stunned gallery to keep comments and reactions to themselves. The judge called for a short break to give Frank time to compose himself.

'I always thought if I never said it, it wasn't real'

On the interrogation tape, Frank provided more details about the alleged sexual abuse.

"He made me touch him and masturbate him," Frank said. "He made me try to give him head once and I wouldn't do it and he beat the shit out of me. I think I was just 14 then."

Frank said it was around that time that he attempted suicide. "I tell you I wanted to die every day since. I still do."

Court was told earlier that Klaus got Frank hooked on cocaine when he was 14.

Jason Klaus

Jason Klaus smirked in the prisoner's box as he watched co-accused Joshua Frank describe him as a sexual predator. (Alberta Outdoorsmen Magazine )

During the RCMP interrogation, Frank also claimed Klaus blackmailed him after their sexual encounter.

"That's how he got me into running drugs for him," Frank said. "He told me if I didn't do this he was going to go tell everybody how I jerked him off and wanted to make advances at him.

"It just hurts so much to say it out loud," Frank sobbed. "I always thought if I never said it, it wasn't real."

Paradis was sympathetic.

"In his eyes you were vulnerable," she said. "He could do what he wanted, ask you what he wanted. And that explains like a lot of things, right? He had that power, he was overpowering you, right?"

Frank agreed. He claimed Klaus used that same manipulative behaviour to force him to murder Klaus's family.

'He's a puppet master pulling strings'

During the interrogation, the Mounties were still trying to get to the bottom of why Frank went along with Klaus's plan to murder his parents and sister.

"He manipulated you into doing things all your life," Graham said. "This is kind of the final act of this play, so to speak, in this saga between you guys. He's a puppet master pulling strings and you do this."

Frank revealed new details about the meeting the two men had in the months leading up to the murders.

He said Klaus told him he had been cut out of the family's will and was about to get caught for writing fraudulent cheques on his father's bank account. Frank said Klaus's solution was to kill his family.

"Well, after he proposed it, I said no to shooting them," Frank said.

"And he pretty much told me that if I didn't help him that I would be back to the old days only this time it would be worse — tied, beaten and raped. And then I'd have my family killed while I was still tied up and then he would come and kill me after."

Frank said he went along with the plan because he couldn't see another way out.

"You pulling the trigger was just an extension of all the other things he's made you do," Graham said.  

Chilling new murder details  

Frank said the two men drove to the Klaus family farm around 4 a.m. on Dec. 8, 2013. Klaus parked his black Chevrolet Suburban at the end of the lane and the two men began to walk towards the Castor-area farmhouse.

He said Klaus had a gun in his pocket and made him walk in front.

"He stepped right in my footprints everywhere we went right behind me," Frank told the investigators. "Gun loaded, said if I didn't do it, I was the first one shot."  

Frank said the two men walked into the house through the unlocked door. Then they approached Gordon and Sandra's main-floor bedroom. The couple was in bed asleep, facing away from other.

Sandra, Gordon and Monica Klaus

RCMP say Sandra, Gordon and Monica Klaus were all shot in the head in their Castor-area farmhouse Dec. 8, 2013. (Facebook)

According to Frank, Klaus reached around him and turned on the light and told him to shoot.

"I think that's why he turned the light on, he wanted to see," Frank said. "I had no choice. I had to react.

"I shot Gordon and I shot Sandi.

He said he heard noise coming from Monica's room.

"She started screaming, 'What's going on?' I'll never forget that as long as I live."

The two men walked down the hall to her bedroom. Frank said he saw Monica under the blankets sitting up in bed when he got to the doorway.

He said he was glad he couldn't see her face in the darkness.

Frank said he shot her.

"Jason patted me on the back and said, 'Good job. Go get the gas.' "

On his way out of the house, Frank said he could hear "a bit of a gargle" coming from the victims.

"There was just the last breath and that was it."

Setting the fire and shooting the dog

Frank returned with a jerry can filled with aviation fuel. He told investigators he stood at the top of the stairs into the basement and poured the flammable liquid down the steps. He said Klaus started the fire with a butane lighter from right outside the back door.

That's when he said the family dog that had been put outside began to react.

Family dog

The Klaus's dog was shot and killed outside the family farmhouse. (Facebook )

"As soon as he lit the fire, the dog started going nuts," Frank said. "Jason ran to the truck and turned around and shot it. I think he was scared it was gonna come after him."

The two men left the property. Frank said Klaus dropped him off just outside Castor with a small amount of cocaine and a "couple of hundred dollars."

The final two hours of the interrogation tape will be played in court Wednesday. Then it will be up to the lawyers to argue whether the tapes should be admitted as evidence at the trial. It's expected Frank's lawyers will try to stop the tapes from being entered.