The inner workings of Ed Gein, a killer who dug up graves in 1950s Wisconsin, are dissected in a new Netflix series, “Monster: The Ed Gein Story,” leading viewers to wonder about his mental state at the time of his crimes.

Max Winkler, who executive produced and directed six episodes of the series, told TODAY.com the team behind the show tried to tell Gein’s real story as sensitively as possible, while factoring in that he likely had undiagnosed schizophrenia.

“What we try to do is tell this story of a extremely isolated guy, a victim of abuse from his mother, with no one to speak to in 1944 in Plainfield, Wisconsin, who had undiagnosed schizophrenia,” Winkler said on Sept. 30 during the red carpet for the premiere of the series.

Gein was arrested in 1957 after investigators found the body of Bernice Worden, a local hardware store owner, hanging by the heels on his property, according to the Associated Press.

When investigators went inside Gein’s home looking for evidence, they found a house of horrors, including preserved human heads, furniture made of human skin and more, according to the AP.

Gein admitted in interviews with investigators to killing two people and digging up the graves of several women, according to a transcript of the interviews included in the book, “The Ed Gein File” compiled by John Borowski.

A 1957 medical evaluation of Gein described his behavior as “morbid (and) ghoulish … with exhumation of several bodies and the fashioning of masks from the heads,” according to the report, published in Borowski’s book.

After his arrest, Gein was deemed unfit to stand trial and was sent to Central State Hospital at Waupun in Wisconsin, the AP reported. Here’s what to know about Gein’s mental health, including the results from his psychiatric evaluation at Central State Hospital.

Was Ed Gein Mentally Disabled?

Gein underwent a mental evaluation after he was admitted to Central State Hospital on Nov. 23, 1957, for a 30-day observation period ordered by the Circuit Court of Waushara County following his arrest on a charge of first-degree murder, according to a copy of the report included in Borowski’s “The Ed Gein File.”

During the evaluation, Gein scored a 106 on the verbal IQ test and an 89 on the performance IQ test, averaging an IQ of 99 on the full scale, according to the report. (Average IQ is around 100.)

“There are indications that subject is better than average intelligence, but here again is shown inefficient functioning,” the doctors wrote in the report.

The report also called him “intellectually adequate” and noted he had an “average fund of school and general knowledge.” But doctors said “his thinking may be tangential and alogical at times. This is especially true when confronted with emotionally charged stimuli.”

“In general, the impairments would indicate a strong emotional disturbance which would be psychotic in nature,” the report added.

Did Ed Gein Have Schizophrenia?

The staff evaluating Gein in 1957 concluded that he was best diagnosed as a “schizophrenic reaction of the chronic undifferentiated type,” and it had been a process going on for “an undetermined number of years.”

Undifferentiated schizophrenia is an outdated term for when a person meets the criteria for the disorder, but doesn’t fall into one of its four subtypes, according to Verywell Health.

Schizophrenia is a serious mental health condition that can result in hallucinations, delusions and disorganized thinking and behavior, according to the Mayo Clinic. People with the disorder can lose touch with reality, and many don’t know they have it.

In the report summary, doctors noted that Gein “had been withdrawn, limited in his contacts over a period of years and failed to develop emotionally in a normal manner” and that he “may have hallucinated on some occasions.”

Gein described “an outside force” that was uncontrollable and evil in nature, and influenced him to dig up graves and “in carrying out the fate” of Worden,” according to the report.

He also told investigators he heard his mother’s voice “telling him to be good” several years after her death, and on one occasion, experienced “what was probably an olfactory hallucination, in that he smelled what he thought was decaying flesh in the surrounding environment of his property.”

“Upon occasion, he stated that he has seen faces in piles of leaves,” doctors wrote in the report.

Ultimately, the report concluded: “Because his judgement is so influenced by his envelopment in a world of fantasy, he is not considered to know the difference between right and wrong.”

Was Ed Gein Ever Imprisoned?

No, Gein was never imprisoned.

The doctors evaluating him in 1957 found that he was not able to stand trial for the murder of Worden. Gein remained at Central State Hospital until 1968, when he was found competent and tried. A judge ruled that Gein was innocent by reason of mental disease or defect, according to the AP.

In 1974, Gein asked for his freedom in sanity hearing, but the judge sent him back to Central State Hospital. Four years later, Gein was transferred to the Mendota Mental Health Institute, where he remained until his death from respiratory failure at age 77 in 1984.