A cold-blooded killer was executed on Tuesday for the rape and murder of a young mother who desperately called 911 while tied up in his backseat. 

Michael Lee King, 54, was executed by lethal injection and pronounced dead at 6.13pm at Florida State Prison, which is about 45 miles outside of Jacksonville. 

He had been convicted of first-degree murder, sexual battery and kidnapping. The heinous crime was committed against 21-year-old Denise Amber Lee in 2008. 

As the three-drug injection entered his bloodstream, the vile murderer began breathing heavily and his body began to twitch. Minutes later, he stopped moving. 

After the warden shook King and shouted his name, a medic in the execution chamber then pronounced the killer dead. 

The woman’s family members, including her husband, eldest son, parents and siblings, witnessed the execution. All of them wore pink, her favorite color. 

At a press conference outside the prison after the execution, Lee’s husband, Nathan, said: ‘Finally, it’s over, this chapter is closed.

‘I’m just super blessed that I got to know Denise, let alone marry her and have two amazing kids with her. 

Michael Lee King, 54, was executed by lethal injection in Florida State Prison on Tuesday evening. He had been convicted of first-degree murder, sexual battery and kidnapping

King’s victim was 21-year-old Denise Lee, a married mother of two. He raped and murdered her in January 2008

Following King’s execution, Lee’s husband, Nathan, said he was ‘blessed’ to have met his wife and had two sons with her. The family is pictured in a still from an ABC 20/20 episode

‘I’m glad this day is done, and now we can focus on what we’ve been focusing on for the last 18 years, and that’s moving forward and trying to bring positive change to 911 and other things.’

Nathan was referring to the fact that a series of 911 calls on the night of his wife’s murder went unaddressed due to communication failures.

Lee’s death led to the Denise Amber Lee Act, which mandated better training for 911 operators in Florida. 

Nathan created a nonprofit called the Denise Amber Lee Foundation after his wife died, and the organization’s efforts led to the creation of the act, which was unanimously passed by the Florida State Legislature in April 2008. 

Court records described the horrific night that Lee was murdered and detailed King’s monstrous crimes. 

On January 17, 2008, Lee was outside her home in North Port, which is near Sarasota. She was with her sons, two-year-old Noah and six-month-old Adam.

King, then 36, drove by and spotted her before returning later when her children were back inside the house, and he kidnapped the young mother.

He took Lee to his home, where he tied her up and raped her. He then forced her back into his car and drove to his cousin’s house to borrow a flashlight, shovel and gas can. 

Nathan created a nonprofit to promote better training for 911 operators after there were communication failures on the night of his wife’s murder. He is pictured with one of his sons 

Lee’s sons were two years old and six months old at the time she was murdered. The mother is pictured with her young children

While Lee was bound in King’s car, she managed to hide some of her hair under the seats so that investigators would have her DNA, and she hid her ring as well. 

She also managed to find her murderer’s phone and called 911 from it. There is a blood-curdling recording of some of her final moments, when she desperately asked for help and pleaded to be able to see her husband and sons again. 

In the call, she can also be heard begging her captor to let her go after he came back to the car and found her on the phone. 

King callously and cruelly ignored the young mother. He drove her to a remote area in North Port, shot her in the face and buried her. 

A state trooper pulled King over shortly after, as his 1994 green Chevrolet Camaro matched the description given by another 911 caller who had heard screams coming from the vehicle and believed a child had been abducted. 

A total of five 911 calls related to Lee’s murder were made that night, including the one she placed herself, as well as one placed by her husband and three bystanders who saw parts of the crimes unfold, according to the Denise Amber Lee Foundation.

Nathan had placed his emergency call when he came home from work and saw that his children were alone and his wife was nowhere to be found.

King’s final meal consisted of pizza, ice cream and soda. Just before being executed, he gave a nearly inaudible final statement that was relayed by Florida Governor Ron DeSantis’s office. 

Lee left a trail of clues that led to her murderer’s capture and execution, and she managed to call 911 from King’s phone while she was bound in his car

Lee’s two sons, Noah and Adam, are now young adults. Noah, the eldest, said he still feels the loss of his mother

‘Since finding Jesus in prison, I have tried to live as His disciple obeying the Two Great Commandments: To love God with all my heart, my mind and all my being, and to love my neighbor to include everyone — my family, Denise Lee’s family, everyone in the gallery,’ as well as Catholic volunteers who visit the prison and ‘those on the team to end my life,’ the murderer said. 

Lee’s father, Richard Goff, pointed out that King did not apologize for his heinous crimes at the press conference following the execution. 

‘If you can’t say something from your heart, don’t say it,’ the father said. ‘Michael King chose his path and that’s where we ended up today,’ he added. 

Goff described his daughter as a phenomenal person and emphasized her quick thinking and heroic actions that led to her murderer’s capture, and ultimately, his execution. 

‘Denise put him where he’s at because she outsmarted him,’ the father said. 

‘She actually hid hair samples so they’d have DNA in that car, hid them under the seat. She hid her ring in the car so we’d have positive identification that she was in the car. She put handprints in that car,’ he continued. 

Lee’s father, Richard Goff, pointed out that King did not apologize for his heinous crimes in his final statement, and he praised his daughter’s quick thinking that led to her murderer’s capture

‘She did everything in her power to save her life, and he chose to end it.’

Noah, now a young adult, said he still feels the loss of his mother. ‘I unfortunately didn’t get the opportunity to know her and be raised by her,’ he said. 

On Monday, the US Supreme Court denied King’s final request for a stay of execution without comment.