While nothing official has been signed, DiCaprio is rumored to have given a preliminary "yes" to the film, according to Deadline, with a deal supposedly closing soon.
While the film has yet to be cast, it does already have a release date of Aug. 9, 2019.
That date coincides with the 50th anniversary of Sharon Tate’s murder at the hands of the Charles Manson's followers.
Tarantino reportedly has asked I, Tonya actress Margot Robbie to play the role of Tate, and he is also said to be looking at actors such as Tom Cruise and Brad Pitt for two undisclosed "meaty" roles.
DiCaprio will be playing an "aging actor" during the time of the murders, but nothing more than that is know about his role at this time.
Manson himself spent the remainder of his life behind bars for his role in the horrible crimes that were carried out in his name by his "family," passing away just last year.
Tony LaMontagne, the grandson of Leno LaBianca who, along with his wife, were murdered by Manson's family of followers that fateful night spoke out about the cult leader's death and revealed that he found out after an official representative of the prison notified him.
"My initial reaction was somewhat indifferent, as a matter of fact," LaMontagne said. "You would think there would be some sort of … closure now but there really isn't. We are glad that nature took its course and did what the state of California should have done."
LaMontagne went on to say that any time Manson or his followers turn up in the news, the old wounds of his loss are reopened. "It's like putting a Band-Aid on the cut that just about heals and you rip it off and it tears it open again."
"From a 10-year-old's perspective, you lay in bed at night running through: 'What was it like? What happened? What was going through my grandfather's mind,'" he said, explaining that he has been processing the terrible murder of his grandfather since he was a child.
Finally, LaMontagne suggested to reporters that he strongly opposes any of Manson's followers being released for any reason.
"This is an ongoing thing," LaMontagne stated. "He's gone but they are still three people that went into our home that murdered my grandfather and his wife that are still in prison that the State of California is strongly considering paroling."