When two New York City teachers, Jonathan Crupi and Simeonette Mapes, first met outside of school where they taught, it was a textbook lesson in love.

The Mapes say it was one of the happiest days of Simeonette's life when she married Crupi. The newlyweds moved to a condominium, Jonathan started studying for his master's degree. For all intents and purposes, Simonette's parents believed she was living happily ever after.

On July 5, 2012, Simeonette was pushed down a flight of stairs at their home and stabbed 15 times, killing her.

Jonathan Crupi tells police he returned home from running morning errands to find the house trashed and his wife dead at the bottom of the stairs. Jonathan frantically calls 911, and then the Mapes. It looks like a bungled home invasion.

Was her murder gang-related because she had been a witness to something in her neighborhood? Within hours detectives have determined the crime scene was anything but a home invasion.

At Simeonette's funeral, Jonathan wept like a baby and placed two roses on her casket. It was a far cry from what her parents say was his immediate reaction to Simeonette's murder, when they pressed him for answers.

"'John, I want you to think, who could do this?' And he says, 'We need to get beyond this,'" said John Mapes, Simeonette's father.

"That's how we knew. 'Uh oh, there's something wrong here.' There were no tears, there was no emotion, nothing," said Simeonette's mother, Theresa Mapes. "He was more annoyed that the cops were bothering him."

The Crupis were only two days away from their fifth wedding anniversary when she was found at the bottom of the stairs of their condo, savagely stabbed 15 times in the back and neck.

Little did Theresa and John Mapes know that police were zeroing in a prime suspect: Their son-in-law.

Investigators found Crupi had been searching the Internet for "how to throat slash" and "what destroys DNA."

"He had done some Google searches, 'How to stab somebody,' 'How to clean up a crime scene, to use Clorox for DNA,'" said defense attorney Mario Gallucci.

"He had an affection for prostitutes," said Gallucci. "He used the money that he got to go to school to pay for the prostitutes' services. Now, does that make him a killer? No. Does it make him a horrible husband? Absolutely."

Authorities tell Simeonette's parents Jonathan did kill their daughter in a frenzied rage, all because she confronted him about his serial philandering with hookers, and that he lied to her about completing his master's degree.

"Simeontte had done a search on a phone number, and that phone number led back to the escort," said Galluci.

Prosecutors say after stabbing his defenseless wife 15 times, Crupi calmly calls up his favorite prostitute, named "Miss Pumpkin."

Miss Pumpkin testified at his trial that on the day of Simeonette's murder, Jonathan had phoned her for a "quickie." She claims it was an unusual request, that he would always book in advance for motel sex. When Jonathan got there, Miss Pumpkin testified, he asked her if she had seen the news about a teacher being murdered.

The trial of Jonathan Crupi lasted five weeks, but in the end the jury deliberated for just two hours, finding him guilty of second-degree murder. He was sentenced to 25 years to life.

At his sentencing Jonathan Crupi addressed his wife's family, saying: "My lies and infidelity should never have played out in such a public forum. I'd like to apologize to my wife's family. There is one thing I cannot apologize for. I did not kill her. I am an innocent man."