A neighbor recalls hearing gunshots and calling 911 the night Kedarie Johnson was killed. A retired nurse, she thought she could help, but it was too late for Johnson.

An outgoing, gender-fluid teenager is gunned down in a small town in Iowa. Was hate the motive?

A friend and mentor to murdered genderfluid teen Kedarie Johnson quoted LeAnn Rimes song "I Hope You Dance" at his funeral. She said she spoke about the happiness he had and brought to life.

Kedarie Johnson's neighbor John Vanhook says the murder fractured the town. He has even heard people saying the teen deserved it for trying to "pull the wool over people's eyes" about his gender.

Kedarie Johnson's killers bleached his body, leaving no DNA — only some blue fibers. "If we could find those blue fibers, we were one step closer to solving this case," an investigator recalls.

Michelle Castillo is remembered for her warmth and Southern charm. Her mother, Judy Barnickel, says that she and her husband Braulio were like a "couple of smitten kids" at first.

Police looked into a suspicious blue van near where Kedarie Johnson's body was found, but soon realized it was a dead end. "We were back at square 1," an investigator recalls.

Kedarie Johnson's mother, Katrina, says she remembers him coming home one day after coming out, and he had been punched in the face. The adversity just made Kedarie more who he was though.

Oxygen.com Correspondent Stephanie Gomulka speaks to former prosecutor Loni Coombs, Burlington police Sgt. Eric Short, and Georgia Bureau of Investigation Special Agent Rebecca Herold about motivating factors in homicides. The series “Killer Motive” explores different cases with hosts Stephanie Gosk and Troy Roberts.

When Michelle Castillo went missing, Braulio brought a neighbor over to look for her. With a protective order against him, he quickly left, and took the kids to school.

During Braulio's trial, friends and supporters of Michelle showed up to court every day wearing orange — Michelle's favorite color.

After the separation, Michelle moved on in her life, training for marathons. Her running coach says she even qualified for the Boston Marathon — a tremendous accomplishment.

A photographer who shot the Castillo family for years as it grew recalls tension between Michelle and Braulio in the later years of their relationship.