Martins was last seen at the Kent State University campus in Kent, Ohio on May 24, 1978. She was a junior at the college that year, majoring in general studies, a good student. She last seen walking from her friends' dormitory building, Dunbar Hall, to her own dormitory, Engleman Hall, at 2:00 a.m. The two buildings were only about 300 yards apart, but authorities do not believe Martins ever returned to her own room at Engleman Hall. Martins was carrying a white imitation leather shoulder bag at the time of her disappearance. She has never been heard from again. She did not have a roommate, so no one missed her until the following evening. It wasn't until two days after she was last seen that campus officials notified her parents she was missing. The initial investigation into her disappearance was hampered by the fact that most of the students had left for the Memorial Day Weekend; Martins herself had planned a trip to New York with two friends.

Martins is not believed to have left of her own accord, as she was apparently happy and involved in campus life in 1978, and none of her loved ones believed she would have run away. She was a dormitory advisor as well as a volunteer counselor at the campus's Pregnancy Information Center. All of her personal belongings, including her eyeglasses, makeup, clothing and money, were left behind in her dormitory room. She vanished a week before spring semester final exams. Martins broke up with her boyfriend of five years not long before her disappearance, but they remained on friendly terms.

After her disappearance, Martins's parents got a tip that she was working as a prostitute in the Cleveland, Ohio area. Martins's brother was able to locate the prostitute and stated she was not his sister, although the woman did bear a striking resemblance to Martins. A psychic consulted by the Martins family stated she'd been abducted and killed by three young men, and her body was dumped from a low-flying plane onto an uninhabited island at least 50 miles from Kent State. The psychic predicted Martins would be found in April or May 1980, but that time came and went without any resolution.

William John Posey Jr. was considered a possible suspect in Martins's disappearance. In 1978, he lived in an apartment about ten minutes' drive from the Kent State University campus. He was using the name John T. Scorpione at the time. In 1980, Posey pleaded guilty to the abduction and murder of an Illinois woman. He was convicted of kidnapping Iris Brown in 1981. Brown, who disappeared in 1976, has never been located. In 2008, Posey admitted he had murdered her. He has never faced charges in Martins's case, but was looked at due to his criminal history and his proximity to where she disappeared.

Martins resided in the 33400 block of York Street in Avon Lake, Ohio when she was not at school. She has two siblings and graduated from Avon Lake High School in 1973. Her case remains unsolved.