The potential serial killer investigation involving gruesome images discovered at the home of a dead pornographer could take a much darker turn if it turns out the sadistic images were being distributed to a wider network, according to a prominent police and forensic psychologist.

Raymond "R.C." Horsch, an 82-year-old who produced brutally themed pornography and books, died last year. 

But after his son Eugene Horsch, 44, was arrested in June on charges involving unlawful firearms and forgery, police made a series of unsettling discoveries at the family home on Chew Avenue in Philly's Olney neighborhood.

The findings include alleged "snuff" videos believed to show multiple missing women and a drum of chemicals hooked up to the water system.

"The fact that the father was involved in the pornographic industry indicates that there may have been, in addition to the sadistic motives that we usually see in serial murders, that there may have been profit in distribution of so-called snuff films," said Dr. Kris Mohandie, a board-certified forensic psychologist.

So far, police say the Horsch home has been linked to the cases of seven missing women, at least five of whom are believed to be dead. No homicide charges had been filed as of Friday.

Philadelphia police have said they found more than a million pieces of digital evidence, including photos and videos, inside the home. As of Friday, they'd only reviewed less than a third of it, and they've reportedly identified four of the missing women in those images.

Two have been publicly identified: Gabrielle Amarando and Maribel Fresses.

The video evidence was particularly alarming to Mohandie.

"This may very well be in addition to all the heinous alleged crimes that seem to be part of this — you know, abduction, rape, torture and so forth, things that sadistic offenders will do to victims — there may very well also have been a participation in distributing so-called snuff films to underground networks of people that are into this stuff," Mohandie said. "It's scary, and I'm hoping that the investigators are able to resolve some of those questions."

At the time of Eugene Horsch's arrest in the spring, authorities had alleged a woman with him was carrying the ID of one of the missing women.

Excavation crews have been seen searching outside and under the home, including the sewers.

The younger Horsch has not been charged over the missing women.

The investigation remains ongoing.

Fox News' Alexis McAdams and Kimberly Ruiz contributed to this report.