California student thought she was meeting ex-boyfriend one last time. Instead, he put a bullet in her head

When 18-year-old Catina Rose Salarno arrived at the University of the Pacific in Stockton, California, to begin her freshman year in September 1979, she thought she was starting life anew. She had broken up with her high school sweetheart, Steven Burns, and was excited to pursue her dream of becoming a dentist. But on her first day of college, he surprised her by showing up on campus. He asked to meet her for one last time later that evening, said Catina Salarno's college roommate, Joanne Marks.

"She was not looking forward to meeting with him, but she was looking forward to it being the last time," Marks told "48 Hours" correspondent Erin Moriarty in this week's all-new episode, "The Boy Across the Street," airing Saturday, May 3 at 10/9c on CBS and streaming on Paramount+. "She believed that he would stop bothering her," said Marks.

Around 8 p.m. that evening, Burns led Catina Salarno to a dark and secluded part of campus to talk about their relationship. But when she refused to get back together with him, he pulled a gun from his waistband and shot Catina in the back of the head, leaving her to slowly bleed to death.