One of the lead investigators into the Golden State Killer case revealed on a crime podcast Thursday that a towel draped over the suspect’s monitor left the biggest impression on him.

Paul Holes, an investigator with the Contra Costa County, Calif., district attorney’s office, was one of the few officials who gained access into accused serial killer Joseph DeAngelo’s home, according to SF Gate.

The Golden State Killer separated husbands and wives during his attacks and would force the woman from her bedroom to the living room, according to SF Gate. The serial killer then would turn the TV on and keep the sound off, and drape a towel over the screen to give himself a glow to see his victim.

Holes told the “My Favorite Murder” podcast that a towel he found in DeAngelo’s home April 24 “left the biggest impression on him.”

“He has a computer there, and he's got a towel over the monitor,” Holes said. “And I'm looking at that going, ‘Is that just a dust cover, or is he reminiscing?’ He wants a glow. Is he pulling out any of those souvenirs and replicating the glowing environment from back in the 1970s?”

DeAngelo, 72, was arrested last month and was charged with eight counts of murder in Sacramento, Orange and Ventura Counties. Officials said prosecutors will seek the death penalty against him. Police believe DeAngelo is the notorious Golden State Killer, who is wanted in a dozen murders and nearly 50 rapes over a period from the late 1970s to the mid-1980s.