A new documentary has shared clips from a psychiatrist's sessions with one of Britain's most feared killers.
Robert Maudsley from Toxteth , is currently the UK's longest serving prisoner in solitary confinement, having served 42 years for the murder of four men in the 1970s.
Maudsley carried out his own wave of vigilante justice, even killing three of his victims while in prison and reportedly ate part of the brain of one of his victims.
In the chilling tapes, Mausley, now 66, admitted he is "capable of anything" as he spoke to Dr Bob Johnson.
He said: "What you are wanting to do, you are wanting to get into a room and feel the emotions of the childhood but we realised there's certain hazards to actually doing that, but who do we still get in there?
Dr Johnson: "How would you describe the progress that you're making?"
Maudsley: "The progress of the type, I think you've come more into the room with me, even though at a distance.
"I'm able to talk about thing, a lot more things today, than I was able to say six or nine months ago.
"You see the thing is Bob, well, I say I know, I know in the past when I've tried to sort of face these things, you know, I..."
Dr Johnson: "Go on then, try to face these..."
Maudsley: "I'm just capable of doing anything, Bob.
"And that's why I have got to be cautious Bob, you know."
Dr Johnson: "I know. Absolutely right. You are keeping the speed on these things right, all I'm doing, is saying this is where we are going to move in due course."
Maudsley: "I think what I have been doing, I think I 'm effectively putting in pieces.
"I have to make sure my pieces fit."
The recordings will be aired on Quest Red in The Killer In My Family.
The sessions were recorded at HMP Parkhurst, Isle of Wight in the early 90s, where the prison psychiatrist tried to work out the mind of the 'Britain's Hannibal Lecter' for two years.
Dr Johnson spoke about the first time he saw Maudsley in HMP Parkhurst in the 90s, he said: "I visited the prison in May 1991, and I was taken round, they opened the main cell door and there is a wire mesh door inside that, and there is this gaunt figure looking like Mosses, with this long, black drag hair, miserable as sin, sunken face.
"So I made a mental note, I thought 'that's somebody I am going to have to work hard to get alongside'.
"And it took me two, three years to get permission from the senior medical officer to go into the hospital and start sessions with Robert Maudsley."
He also spoke about how frightened he was of the serial killer when he was alone in the cell with him.
He said: "I overcame his suspicion of people in authority, and he agreed to see me.
"And initially it was quite tricky, because I saw him in his cell and he was sitting on his bed, near the window, and I sat near the door.
"And I said 'if you frighten me, I'm going', so we started talking about his past and got a bit too close and he said, 'my palms are getting sweaty' and I said 'I am out of the door, just to let you know'.
"And we had this understanding, and by that time, he had enough interest in me possibly helping him.
"We got an understanding that's the key and we were working well."
John Farrell - March 1974
Maudsley garroted Farrell, 30, after he picked Maudsley up for sex and showed him pictures of children being sexually abused.
David Francis - February 1977
After being sentenced to life in prison, Maudsley was sent to Broadmoor where he and another inmate, David Cheeseman, locked themselves in a cell with David Francis, 26, a convicted paedophile.
The pair tortured him to death over a period of nine hours.
Salney Darwood - July 1978
After the killing of Francis, Maudsley was convicted of manslaughter and sent to Wakefield prison.
There he lured Salney Darwood, 46, who was serving life for killing his wife, into his cell where he garroted and stabbed him then hid his body under his bed.
William Roberts - July 1978
On the same day, with Darwood's body under his bed, Maudsley tried to invite various other inmates into his cell.
After they all declined he went out and found William Roberts, 55, and serving a seven-year sentence for the sexual assault of a seven-year-old girl.
He stabbed him and hacked at his skull with a makeshift dagger before smashing his head into a wall.
It is reported that Maudsley then walked into the prison officer's room, placing the dagger on the desk and told him roll call would be two people short next time.
*The Killer In My Family is on Quest Red, tonight at 10pm