“Please,” the woman said meekly, “I need to understand what happened to my son.”

Enriqueta Lapexlira clutched a framed photo of her boy, 33-year-old Rodrigo Castillo, during a news conference Monday, begging for someone to help Atlanta police solve his homicide.

Castillo, a Mabelton resident who loved hiking and cross fit, was shot on I-20 one year ago. Police say they’ve interviewed everyone in his life and they’ve come up with no motive and no suspects. He had no known enemies.

When the bullets flew, Castillo was driving home from a date at Kimball House restaurant in Decatur. The woman told police nothing strange happened and she couldn't fathom why someone would shoot Castillo, according to Police Chief Erika Shields.

“We desperately want to solve this case,” the chief said.

Police say Castillo was found collapsed over the wheel of his Volkswagen Jetta, which was mysteriously stopped on the interstate near Martin Luther King Jr. Drive. Cops found three 9mm shells. It was shortly after midnight on Aug. 3.

An Emory University grad, Castillo worked as an analyst for a logistics firm in Atlanta. He enjoyed the work and his co-workers. He was good at endearing himself. Once, he scoured candy shops in Mexico for special beer-shaped lollipops, not because he wanted them, but because a friend had loved them when she was a little a girl and couldn’t find them anywhere.

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Soon after police found his body, his mother got a call from Grady Memorial Hospital and most everything in her life broke.

“Rodrigo was an adoring son. He was not only my only child but my best friend,” she said. “I miss him every day, every hour.”

He used to call her every other day to chat about their lives, the news, whatever.

The last call came a day before he died. He spoke effusively about his life.

”Everything is perfect,” the son told the mother.