Catherine Zeta-Jones told a court in a faltering voice of the terrifying "satanic" death threats made against her by an alleged female stalker.
The Los Angeles court heard how the Oscar-winning star was on the verge of a nervous breakdown after friends and family members received the threatening letters from unemployed Dawnette Knight.
"I've never in my life had anything or had anyone say anything to me so satanic," said Zeta-Jones in a hearing to decide whether Knight should stand trial.
"I can't even imagine how a sane human being could have these images locked in their brain. This will affect me for the rest of my life."
Zeta-Jones, originally from Swansea, who is married to Hollywood star Michael Douglas, read from 19 letters during the hearing yesterday at Los Angeles Superior Court.
When she was not reading, Zeta-Jones, wearing a long-sleeved black dress, glared at her alleged stalker, who was handcuffed to a chair.
One letter threatened to have Zeta-Jones "shredded to pieces" and another vowed to cut her up "like meat on a bone and feed her to the dogs".
Another letter included an invitation to Zeta-Jones's funeral.
Others referred to the violent deaths of President John F Kennedy and OJ Simpson's wife Nicole Brown Simpson.
It is alleged that Knight, 32, made the threats over an 18-month period because she was obsessed with Douglas.
Zeta-Jones, who won as Oscar for the movie Chicago, said she still lived in fear.
She told how her husband, who starred in the 1987 movie, Fatal Attraction, kept the letters secret from her for a while, to spare her the trauma.
He broke the news at their Bermuda home earlier this year.
"Michael looked at me and said, 'They're pretty bad, honey.' I know my husband and I know that look and I knew it was pretty serious," Zeta-Jones said.
Staff members, friends and relatives, including Douglas's father, film legend Kirk Douglas, received the letters, the court heard.
In March, a Bermuda hotel owned by the couple received two threatening calls.
In mid-May, while Zeta-Jones was in Amsterdam filming for Ocean's 12, the hotel she was staying at took three calls that were "violent" and "shocking to the phone operator", the actress said.
Zeta-Jones said she had a severe anxiety attack on her way to her home in Spain three days later.
She felt faint, was sweating and shaking and had difficulty breathing, she said.
She was particularly scared because the stalker knew details about her movements, the name of her children's nanny and the layout of one of her homes.
"I didn't know where it was coming from. It seemed to be closing in on me and getting closer and closer to home and that in itself was horrific," she told the court.
Earlier, Douglas told how his wife was driven to the brink of a nervous breakdown.
"She just felt that she was a marked person," he said.
"She was having a difficult time maintaining emotional control," he said, recalling that she became "hysterical".
The 59-year-old actor told the court that his wife "showed all the signs of having a nervous breakdown".
He described the threats as "very graphic in nature".
"I've never received mail like this before," he told the court.
"The proximity made us terrified. There was a knowledge in these letters that was deeply unsettling."
Douglas said he took his wife to a doctor when he feared that she would crack under the stress. The doctor prescribed medication to calm Zeta-Jones's nerves.
When police told the couple on June 3 that Knight had been arrested at home in Beverly Hills, Zeta-Jones broke down in tears of relief.
Knight, who is in custody, is engaged and wants to be a child psychologist.
She is charged with 25 counts of stalking and making criminal threats against 34-year-old Zeta-Jones.
If tried and convicted, she could face a sentence ranging from probation to 19 years in prison.
Knight has already apologised for sending letters to the Douglases.
In a letter sent last month, she said she was a "confused young woman", obsessed with Douglas.
Her lawyer Richard Herman said previously that Knight had a "girlish crush on Michael Douglas" and sent him a note telling him she would show him "a good time".
But he was "not convinced my client wrote all the letters".