New court documents released on Thursday allegedly show suspected Gilgo Beach serial killer Rex Heuermann’s meticulous planning to prepare, commit and get away with murder.

The disturbing and detailed manifesto was found on one of Heuermann’s 58 hard drives that investigators recovered during their initial search of his property in 2023. Prosecutors said that, in the document, Heuermann “plans out” his “kills” by creating a checklist of issues to avoid getting caught, needed supplies and potential dumping sites.

“His intent was specifically to locate these victims, to hunt them down, to bring them under his control and to kill them,” said Suffolk County District Attorney Ray Tierney.

The Microsoft Word document was recovered using a computer forensic extraction method. It was found in an “unallocated space,” which means someone had deleted it. A forensic analysis concluded that the document was created in 2000 and had been modified between 2001 and 2002.

It allegedly references slayings that prosecutors believe likely happened inside Heuermann’s Massapequa Park home. It notes steps to take “next time,” such as “hit harder” and “consider a hit to the face or neck for takedown.”

Under a list labeled as “SUPPLIES,” Heuermann allegedly wrote down cutting tools, acid, hair nets, and tarps.

“We allege that the methodology, that the exact method by which these murders were committed in excruciating detail in that document, is in some cases identical to the methodology used to murder the six victims in this case,” Tierney said.

Heuermann allegedly listed Mill Road on the document, an area in Manorville where police first found partial remains of Gilgo Beach victims Valerie Mack and Jessica Taylor, as a potential dumping site.

Prosecutors said Heuermann’s planning document included a list labeled “BODY PREP." It states tasks such as “remove head and hands, remove trace DNA and remove ID marks [like] tattoos.”

The contents are consistent with the condition of Mack and Taylor’s remains in 2000 and 2003. Their torsos were discovered in Manorville and more of their remains were found along Ocean Parkway in 2011. Also, Taylor’s tattoo had been mutilated in, what investigators believed at the time, an attempt by her killer to cover up anything that might identify her.

The document also stated to “use push pins to hang drop cloths from ceiling” and “use heavy rope for neck-light rope broke under stress of being tightened.” These details are what brought detectives back to Heuermann’s home for a renewed search in May.

“Once we received that document, we went back into the house and, looking at the paneling in the downstairs basement area, we were able to look through an infrared light and establish a cordoned-off area where an adhesive had been placed,” Tierney said. “We also found an area where there were push pins into the drop ceiling.”

The bombshell manifesto included another checklist titled “THINGS TO REMEMBER.” It displayed concerns that “SOUND TRAVELS,” which prosecutors believe indicates the incidents likely occurred indoors.

Investigators said Heuermann opines on the importance of sleep in the document, not only to avoid problems but to increase what Heuermann refers to as “PLAY TIME.”

The hard drive containing the once-deleted document is one of dozens of electronics investigators seized during their search warrants. Among the electronics recovered—which investigators are still going through—include 58 hard drives, 27 computers, 46 cellphones, 16 cameras, nine WI-FI routers, 17 tablets, 42 USB drives, eight laptops, 50 hotel cards and four GPS devices.