WOULD A HUSBAND DRUG HIS KIDS SO THEY WOULDN'T HEAR HIM KILL HIS WIFE? "48 HOURS: "SHATTERED DREAMS" - SATURDAY, JAN. 5, 10:00 PM, ET/PT

From the outside, David and Karina Ditto seemed to have the perfect marriage. They met in 1993 while he was on a college vacation in Mexico. They fell in love. She moved to the United States to be with him, where they married, had kids, and created what seemed like a dream life.

Behind the facade, however, it was believed they had crumbling marriage fraught with problems most outsiders knew nothing about. The dream life was shattered in March 2011, when David frantically called 9-1-1 saying his wife had fallen down a flight of stairs and slammed her head on a tile floor. The first emergency medical responders on the scene found Karina's bloodied, lifeless body. She died two days later. The investigation into her death would reveal a life of extreme emotional and control abuse allegedly inflicted on Karina by the man of her dreams.

First responders were immediately suspicious of David's version of what happened because of the extent of Karina's injuries and where her body landed from the alleged fall. He also maintained he attempted CPR, though first responders didn't believe him. "She had so much blood on her face that if he had put his mouth over her mouth, he would have had her blood on his face," first responder Lisa Challender says.

David Ditto repeatedly told police that night that Karina's injuries were because of the fall, nothing else. "I heard the cat screech at the top of the stairs and I heard a horrible falling down the stairs," he tells 48 HOURS Correspondent Maureen Maher in "Shattered Dreams" to be broadcast Jan. 5, 2012 (10:00 PM, ET/PT) on the CBS Television Network. "And I jumped up and ran over, and found Karina laying at the foot of the stairs. She wasn't moving - wasn't talking."

The San Diego County medical examiner ruled Karina was beaten and strangled and soon after David Ditto was charged with his wife's murder. The investigation exposed red flags that suggested Karina's death was no accident. Moreover, investigators learned Karina had written letters to her mother saying David would tell her which spoon to use, when to eat and how much water to use for houseplants. "He punishes me with money, he takes it away for months," Karina wrote to her mother. "Sometimes I don't know why I married him," she wrote.

Veteran homicide detective JC Smith tells Maher that police also questioned why the children, asleep upstairs in the home, never woke up given the number of EMS, fire and police workers in the home. "David had access to narcotics, and we thought, possibly, he used the drugs on his kids," Smith tells Maher. "Absolutely not," Ditto says.

Maher and the 48 HOURS team report on Karina Ditto's death and follow the case through David Ditto's trial for murder, using interviews with David, his attorney, his mother, her mother, prosecutors, friends and others. "Shattered Dreams" is produced by Deborah Grau, Gayane Keshishyan, Alec Sirken and Cindy Cesare. Sarah Denlinger is the associate producer. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

"Shattered Dreams" is the second of a 48 HOURS double feature to be broadcast on Jan. 5. The first, "Ransom," features Peter Van Sant's updated report on the disappearance of Lakeland, FL airline worker, Robert Wiles, and the $750,000 ransom demand made on his millionaire father, Tom Wiles, to get him back. "Ransom" (9:00 PM, ET/PT) is produced by Allen Alter and Paul LaRosa. Peter Schweitzer was the senior producer. Linda Martin is the update producer. Susan Zirinsky is the senior executive producer.