The book says he tried to use his young daughter to cover up the crime.
It was the crime that shocked America.
A doctor called 911 after finding his wife's body in the bathtub.
Called: "She just had surgery a week ago."
911 operator: "What kind of surgery did she have?"
Caller: "A facelift."
It was dubbed 'the facelift murder case.
Dr. Martin MacNeill, a prominent Utah physician was charged with murdering his beautiful wife, Michelle, all so he could be with his 29-year-old mistress.
Now, author Shanna Hogan reveals riveting new details in her new book The Stranger She Loved: A Mormon Doctor, His Beautiful Wife, And An Almost Perfect Murder.
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Hogan told INSIDE EDITION's Les Trent, "He thought he could get away with murder if he made it look like an accident."
Trent asked, "You wrote that shortly before the death, Michelle was suspicious of her husband. What did she ask her daughters to do in terms of investigating?"
Hogan replied, "One of the most emotional parts the book and the thing that really stuck was, 'If anything happens to me, makes sure it wasn't your dad.' "
MacNeill and Michelle lived in a stately home with their children, until he began a torrid affair with a nursing assistant named Gypsy Willis, who spoke exclusively with INSIDE EDITION.
Willis said in court during the trial, "He told me he had a perfect marriage. That she was beautiful. His kids were perfect. He wanted some excitement in his life."
MacNeill became obsessed with Gypsy Willis and was bent on murder when he asked his 49-year-old wife to get a facelift to freshen up her looks. Following the facelift procedure, MacNeill gave Michelle a combination of powerful drugs.
"Percocet. Ambien. Valium. All depressants that would have made her groggy go to sleep," said Hogan. "He helped carry her to tub. Once she was in the tub he put her face in the water and held her there until she drowned."
Hogan writes that MacNeill used their 6-year-old daughter to help cover his crime.
"Instead of Michelle picking up his daughter from school, he was the one who picked up his daughter from school, brought her in the house, waited in the kitchen and urged her to look for her mother," said Hogan.
MacNeill sounded panicked when he called 911.
Operator: "Who's in the bathtub?"
MacNeill: "My wife!"
911 Operator: "Is she breathing at all?"
MacNeill: "She is not!"
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The author says Dr. MacNeill almost got away with the perfect murder.
"The police ruled it an accident, that she had heart disease and it was a natural cause of death," said Hogan.
Two months later, MacNeill actually had the nerve to move Gypsy Willis into the house, ostensibly to work as the family nanny. That aroused the suspicion of his adult daughters.
Hogan explained, "Alexis and Rachel fought tirelessly, went to the police, went to the media before finally getting the attention of the County's Attorney's office and seeking a criminal case against their father.
MacNeill's daughters broke down and sobbed in court at their father's murder trial in 2013. Justice for their mom was finally at hand.
"Martin almost got away with this. He clearly almost got away with murder. If not for the perseverance of his family he would be free today," said Hogan.
Willis says she did not know MacNeill planned to kill his wife and was not charged.
