MATURE CONTENT WARNING: This story contains descriptions of gruesome crime scenes.

Some of Michigan's most notorious homicide cases — often referred to as the Michigan Murders and Coed Killings — have mostly remained a mystery for more than 50 years. Police aggressively investigated the slayings in the late '60s as body after body turned up in Ypsilanti and Ann Arbor and newspapers nationwide carried the headlines.

Finally, in 1969, police caught a break and arrested John Norman Collins.

The handsome Eastern Michigan University student was convicted of only one murder, the last one. More than 35 years later, another man was found guilty of one of the other slayings that Collins was suspected of committing. This prompted authorities to re-examine the other cases and generated new information.

The Free Press gathered never-before-seen evidence that was collected in the 1960s. See for yourself:

Map of murder scenes published by the Detroit Free Press in July of 1969. Detroit Free Press

Mary Terese Fleszar, 19, of Willis

Mary Fleszar, 19, of Willis was found dead near Geddes and LeForge roads between Ann Arbor and Ypsilanti, Michigan, on Aug. 7, 1967. Free Press File Photo

Body found on Aug. 7, 1967: The Eastern Michigan University accounting student was the first of eight victims whose slayings would terrify Michiganders and a nation in the midst of cultural upheaval. When her brutalized body was found, authorities had to use dental records for identification.

Michigan State Police

She was the first victim.

She took a walk on July 9, 1967, near Eastern Michigan University’s campus.

A month later, her badly decomposing body was found near Geddes and LeForge roads.

She had been stabbed. Her feet were cut off. Her clothes were left piled up nearby.

Joan Elspeth Schell, 20, of Plymouth

Joan Elspeth Schell, 20, of Plymouth went missing on June 30, 1968 and was found dead near Glazier Way and Earhart Road on the outskirts of Ann Arbor a week later. Free Press File Photo

Body found on July 5, 1968: She was last seen hitchhiking near the EMU student union on June 30, 1968. Days later, her body was found just outside Ann Arbor. Her throat had been stabbed and slashed, and her blue miniskirt was twisted around her neck.

Crime scene photos from the Schell case. Crime scene photos from the Schell case. Crime scene photos from the Schell case. Michigan State Police

Jane Louise Mixer, 23, of Muskegon

Jane Louise Mixer, 23, of Muskegon was found dead in a cemetery in Denton Township, Michigan on March 21, 1969. Yearbook photo. Free Press File Photo

Body found on March 21, 1969: The University of Michigan law student was last seen on March 20, 1969, trying to get a ride home to Muskegon. The next day, her body was found in a Denton cemetery. She had been shot in the head. In 2004, DNA evidence linked her to Gary Leiterman. He was convicted of murder. The case led State Police to re-examine some of the other cases.

Show caption Hide caption Michigan State Police Det. Sgt. Eric Schroeder is profiled against his computer screen showing a picture of Jane Mixer taken in 1968 while in his... Michigan State Police Det. Sgt. Eric Schroeder is profiled against his computer screen showing a picture of Jane Mixer taken in 1968 while in his office on Friday, July 8, 2005. Schroeder found the old picture of Mixer from the evidence collected during the investigation of her March 1969 murder, her body was found in the Denton cemetery. ERIC SEALS, Detroit Free Press

Maralynn Skelton, 16, of Romulus

Maralynn Skelton, 16, of Romulus was found dead near Glazier Way and Earhart on the outskirts of Ann Arbor on March 25, 1969. Free Press File Photo

Body found on March 25, 1969: She had been seen hitchhiking near Arborland Shopping Center in Ann Arbor on March 24, 1969.

Michigan State Police

The next day, her body was found near Glazier Way and Earhart.

In 2009, Michigan State Police took new evidence photographs of the contents of her purse.

Items included things like lipstick, keys, sunglasses, and a change purse.

Along with Skelton’s personal items was a small photo album.

The collection of photos had messages from friends written on the back.

Top: "Maralynn, To a real cool girl with a swinging personality. Good luck with the guys. A.B.C. Frank"

Bottom: "Eternity. Hours Fly. Flowers Die. New Days. New Ways. Pass By. Love Stays."

“Marlyn,(sic) To a girl who is both sweet and had a great personality. Good luck in the future. Terry, '70' ”

Dawn Louise Basom, 13, of Ypsilanti

Dawn Louise Basom, 13, of Ypsilanti was found dead near Gale and Vreeland roads in Michigan on April 15, 1969. Free Press File Photo

Body found on April 16, 1969: She was the youngest victim. Dawn was last seen on April 15, 1969 near EMU. The middle-school student's body was found near Gale and Vreeland roads. She was strangled and her body slashed. Some of her clothing was later found in an abandoned farmhouse.

Crime scene photos from the Basom case. Crime scene photos from the Basom case. Crime scene photos from the Basom case. Michigan State Police

Alice Elizabeth Kalom, 21, of Portage

Alice Kalom, 21, of Portage went missing on June 7, 1969 and was found dead near North Territorial Road and U.S. 23 in Michigan. Free Press File Photo

Body found on June 9, 1969: She was last seen dancing at a party in Ann Arbor on June 7, 1969.

Michigan State Police

Two days later, her body was found near North Territorial Road and U.S. 23.

She was shot in the head and stabbed in the heart. Her clothes had been ripped off and scattered.

Her shoes were missing.

Karen Sue Beineman, 18, of Grand Rapids

Karen Sue Beineman, 18, of Grand Rapids. DFP file

Body found on July 26, 1969: She was last seen at a wig shop in Ypsilanti on July 23, 1969. Her naked body was later found in a ravine off Riverside Drive near the Huron River in Ann Arbor Township. She was strangled, and her face was beaten so badly it was unrecognizable. John Norman Collins was convicted of murdering her.

Crime scene photos from the Beineman case. Michigan State Police

It took years to catch the killer who left two Michigan college towns paralyzed with fear, but their search lead them to an unlikely suspect. Clean-cut, handsome, and a good student, behind that exterior was a man described by the victims' families as a monster.

John Norman Collins, 22, of Center Line

Michigan State Police

Collins, a 22-year-old Eastern Michigan University student, never fit anyone's image of a killer.

Handsome and clean-cut, he graduated from a Catholic high school, was football team captain and was studying to be a teacher.

Collins was a suspect in the slayings, including an additional one in California.

After his arrest in 1969, the killings stopped. At trial, a jury convicted him of murdering 18-year-old Karen Sue Beineman.

Police tried to catch Collins for two years.

Collins loved motorcycles, a detail that later would come up at trial and decades later in prison interviews with State Police detectives.

MORE IN THIS SERIES

THE EVIDENCE LOCKER: What police discovered at 7 Michigan murder crime scenes

CHAPTER 1: Never-before-published letters, interviews offer clues in infamous Michigan murders

CHAPTER 2: Murders of Michigan women still unsolved 50 years later — but cops had eye on 1 man

CHAPTER 3: 'Handsome' EMU student was unlikely serial killer suspect. Letters, interviews reveal dark side.

COLLINS' LETTER: John Norman Collins — one of Michigan's most notorious killers — pens letter to the Free Press