Overview

Last seen: November 14, 1970
Location: Highland City, Polk County, Florida
Age: 25
Status: Endangered missing; foul play suspected

Cook was reportedly at her Highland City home before an intended shopping trip to the J.M. Fields department store in Lakeland. Her husband said she planned to buy Christmas presents for their sons, who were five and three years old. However, investigators later noted that no independent witness could confirm seeing Mary—or her car—at the store that day.

Her white 1959 Cadillac was discovered in the J.M. Fields parking lot the following day. Mary’s purse and wallet were inside, but approximately $200 that her husband said she had been carrying was gone. Her wedding rings, which she reportedly wore consistently, had been left at home. Those circumstances eventually contributed to investigators treating the disappearance as suspected foul play rather than simply a voluntary disappearance.

Detailed Case Breakdown

Mary Margaret Cook Disappearance: The Unsolved 1970 Highland City, Florida Case

Mary Margaret Cook was 25 years old and the mother of two young boys when she vanished from Highland City, Florida, on November 14, 1970. More than five decades later, her disappearance remains unresolved, and investigators have long suspected foul play. She has never been located, and no one has ever been charged in connection with her disappearance.

Brief Case Summary

Last seen: November 14, 1970
Location: Highland City, Polk County, Florida
Age: 25
Status: Endangered missing; foul play suspected

Cook was reportedly at her Highland City home before an intended shopping trip to the J.M. Fields department store in Lakeland. Her husband said she planned to buy Christmas presents for their sons, who were five and three years old. However, investigators later noted that no independent witness could confirm seeing Mary—or her car—at the store that day.

Her white 1959 Cadillac was discovered in the J.M. Fields parking lot the following day. Mary’s purse and wallet were inside, but approximately $200 that her husband said she had been carrying was gone. Her wedding rings, which she reportedly wore consistently, had been left at home. Those circumstances eventually contributed to investigators treating the disappearance as suspected foul play rather than simply a voluntary disappearance.

Who Was Mary Margaret Cook?

Mary Margaret Cook was born April 26, 1945. At the time she disappeared, she was approximately 4 feet 11 inches tall and weighed between 145 and 150 pounds. She had brown hair, blue or hazel eyes, wore cat-eye eyeglasses and reportedly could not see well without them. She also had a birthmark above the outside of her right ankle. Records describe her as White and Native American.

She may have been wearing a green dress when she disappeared. Early newspaper reporting described the garment more specifically as a homemade green dress trimmed with white lace and a matching green tie. Some case records also state that Mary may have been pregnant at the time.

Mary was a stay-at-home mother. Her husband, Leathern “Earl” Cook, frequently traveled to the West Palm Beach area for painting work during the week and returned to Highland City on weekends. The couple had been married approximately eight years when Mary disappeared.

What Happened on November 14, 1970?

According to the account attributed to Earl Cook, Mary left their Highland City residence on the evening of November 14 to shop at J.M. Fields on North Lake Parker Avenue in Lakeland. She was supposedly carrying approximately $200 to purchase Christmas presents for the couple’s children.

That account became a significant issue in the investigation because authorities found no independent witness who could verify that Mary actually arrived at the department store. The current Charley Project case summary states that neither Mary nor her Cadillac was seen at the store that day.

At approximately 1 a.m. the following morning, her Cadillac was located in the J.M. Fields parking lot. Early reports said her purse, wallet and identification were present. The money she had reportedly carried was missing.

Investigators initially considered possibilities including robbery or abduction. Newspaper reports from the period said deputies already suspected foul play. Tips and reported sightings were investigated in locations ranging from Sarasota to Chicago, but none produced Mary.

Investigators Focus on Mary’s Husband

As the investigation developed, the Polk County Sheriff’s Office came to view Leathern “Earl” Cook as the principal suspect in Mary’s disappearance. Authorities publicly described him as a suspect during the renewed investigation in 2003. He was extensively interviewed but was never arrested or charged.

Earl consistently denied killing his wife and reportedly told the couple’s children that Mary had abandoned the family. He maintained his innocence until his death in 2007.

The fact that investigators considered Earl a suspect should not be treated as proof that he killed Mary. No criminal charge was filed against him, no court determined responsibility, and Mary’s remains have never been recovered.

Their Son’s Later Recollection

One of the most significant later developments came from Mary’s oldest son, who was five years old when she disappeared.

According to the current case summary, he later recalled seeing his parents arguing that day. He also remembered his father telling him not to look outside. As an adult, he came to believe that his mother’s body may have been concealed inside a red blanket from the house and transported elsewhere.

Those recollections emerged years after the disappearance and therefore should be distinguished from physical evidence established in 1970. Nevertheless, they contributed to investigators’ continuing interest in what may have happened at the Cook residence before Mary’s Cadillac appeared at the department-store parking lot.

The 2003 Search Beneath the Cook Home

The investigation received major renewed attention in March 2003 when Polk County Sheriff’s Office detectives returned to the Cook family’s former Highland City property.

Acting on new information, investigators removed sections of the concrete garage floor and excavated beneath it because they suspected Mary’s body might have been buried there. Earl Cook was interviewed again and provided a blood sample.

The search expanded considerably. Authorities eventually demolished the garage structure so detectives could examine additional ground beneath it. Despite the effort, they found no human remains or evidence establishing that Mary had been buried there.

Polk County officials emphasized at the time that the failed excavation did not close Mary’s overall case. Investigators continued to believe she had likely been killed, although the location of her remains remained unknown.

DNA and Unidentified Remains Comparisons

Later community case records reported another important investigative step: relatives of Mary supplied DNA samples for comparison against unidentified human remains. A Websleuths case discussion reported that a detective obtained samples from Mary’s mother and sister and arranged another kit for her brother. The same discussion said investigators were comparing Mary to unidentified remains discovered near Thonotosassa, Florida.

That information originated in case-community reporting rather than a current official Polk County press release, so it should be treated accordingly.

Subsequent postings citing NamUs data indicated that Mary was eventually listed as an exclusion for the unidentified Thonotosassa woman, meaning that particular set of remains was not considered to be Mary.

Possible Connection to Another Highland City Disappearance

Mary’s case has sometimes been discussed alongside that of Peggy Wynell Byars-Baisden, a 23-year-old mother who disappeared from Highland City in April 1965.

Both women were young mothers of two, lived on the same street, and disappeared only five years apart. Those similarities have understandably generated public speculation.

Investigators, however, have said they have not found credible evidence establishing that the two disappearances are connected. Authorities reportedly did not believe the women knew each other, although they have kept an open mind regarding information supplied about either case.

Latest Publicly Available Investigation Information

As of September 2026, Mary Margaret Cook remains publicly listed as an endangered missing person. No recovery of her remains, arrest, prosecution or confirmed resolution of the case was located in current public records reviewed for this article. The Charley Project continues to list her disappearance as unresolved and states that foul play is suspected.

The most recent case-specific investigator information I located in a publicly accessible source was published in August 2023. It directed information about Mary to Detective Matthew Newbold of the Polk County Sheriff’s Office at 863-298-6834 and listed missingperson@polksheriff.org.

Because individual detective assignments can change, the Polk County Sheriff’s Office’s current official contact page is also important. It lists the agency’s main non-emergency number as 863-298-6200, toll-free 1-800-226-0344, and identifies a Cold Case Homicide Unit contact through ColdCase@polksheriff.org.

The case therefore remains one in which new witness information, family knowledge, previously undisclosed observations or evidence capable of being examined with modern forensic methods could still matter.