Zachary Davis, 15, bludgeoned his mum to death with a sledgehammer as she slept, then set the family home on fire in a bid to destroy the evidence - and kill his brother. He is one of the most unforgettable guests that has ever appeared on Dr. Phil.
I don't care, I'm proud to admit I LOVE WATCHING DR. PHIL! But there is one guest who has forever stayed in my memory, least of all as he speaks even slower than the bald meddler himself, Zachary Davis.
On August 10 2012, Zachary, then aged just 15, when he bludgeoned his mother Melanie Davis to death with a sledgehammer and then torched the family home. He claims he did it after she failed to take his claims of being raped by his older brother Josh, 16, seriously.
When he went to trial in Tennessee, jurors heard a series of hideous statements (before he was jailed for 71 years).
He used a sledgehammer because: "I was worried that I'd miss" and using that type of weapon gave him the "highest chance of killing her".
He set an upstairs room on fire using whiskey and petrol but it failed to burn the whole house.
He was laughing as he bludgeoned his mum to death.
The voice of his dead dad told him to kill his family.
But the whole case becomes even more chilling when you hear it from his own mouth...
Zachary Davis appeared on a special episode of the show in 2015, where Dr. Phil went to visit him in prison and speak to him about his heinous crimes.
It really is not just what you say but how you say it, huh?
There's something about the way he moves, nods upwards, speaks in a monotonous drawl, and glances at Dr. Phil which truly sets me - and most other people - on edge.
Zachary was diagnosed as being schizophrenic and having depressive disorder as a youngster - but looking at him, doesn't it seem almost like he is possessed by a demonic entity?
The monotonous voice, the dark, deep set eyes, the general aura... what do you really think is going on here? Vote in our poll below...