There’s an indisputable fact about Lyle and Erik Menendez: The brothers killed their parents, Jose and Mary Louise “Kitty” Menendez, on Aug. 20, 1989, in the den of their Beverly Hills mansion in California.

But what was the motivating factor behind the murders? Was it greed, as prosecutors contended, or was it retaliation after years of abuse at the hands of their parents, as the brothers alleged?

It is a question that the Netflix series “Monsters: The Lyle and Erik Menendez Story” attempts to answer by dramatizing events and showing different points of view — from the parents, the brothers and those in the family’s circle or some just outside of it.

While the latest iteration of Ryan Murphy’s true-crime anthology series is based on the historical events of the case, including the brothers’ trials (the first ended in a mistrial), it also insinuates an incestuous relationship between Lyle and Erik, something the brothers say is untrue.

Recently, Erik’s wife, Tammi, posted a statement on social media from him about the series and how the brothers were depicted, calling it “inaccurate” and that Lyle’s depiction was a “caricature” that was “rooted in horrible and blatant lies.”

It was followed by another statement from members of the Menendez family, who expressed support for the brothers and called the series a “grotesque shockadrama.”

The statement also disputes the idea of an incestuous relationship, which Murphy said was a theory of Dominick Dunne (played by Nathan Lane in the series), the famed Vanity Fair writer who covered the trials.

“I think it’s faux outrage,” Murphy said in response to the family’s reaction to the series. “I think that this story, this Netflix series, is the best thing that has happened to the Menendez brothers in 30 years because it’s getting people to talk about it, and it’s getting people to ask the questions that are important.”

Among those questions are whether the brothers should have another trial and be freed. Just last year, the brothers submitted a petition for a new hearing based on allegations raised in the Peacock docuseries “Menendez + Menudo: Boys Betrayed” by Roy Rosselló, a former member of the Puerto Rican boy band who said he was drugged and raped by Jose, who was then head of RCA Records. Such testimony could support Lyle and Erik’s claims that they were abused by their father.

Part of Murphy’s goal with the series is to showcase the brothers’ point of view, “uninterrupted and unchallenged, which did not happen in court.” “Monsters” also attempts to contextualize the era and how the brothers became enduring pop-culture figures despite their notorious crime.

“Looking back, I thought it would be very interesting to do something where you were very unclear about who the monster was,” said Murphy, who co-created and serves as co-showrunner. “Were the boys the monster? Were the parents the monsters? And what I came to was, they all were monsters in different ways.”

The series features newcomers Nicholas Alexander Chavez as Lyle and Cooper Koch as Erik, co-starring with Javier Bardem as Jose and Chloë Sevigny as Kitty. “Monsters” has topped Netflix’s most-watched charts since its release on Sept. 19, spurring a flurry of interest in the case and what actually happened.

Over the decades, the Los Angeles Times covered the case, from the initial report of the murders to the trials and sentencing, and what has happened to the brothers since their conviction.

Here are some answers to questions about which moments in “Monsters” were rooted in fact.

Were the brothers inspired by the film “Billionaire Boys Club”?

Throughout “Monsters,” we see Lyle and Erik discuss the 1987 film that’s based on a real-life group called the Billionaire Boys Club, an investing and social club that was led by Joe Hunt in the Los Angeles area in the 1980s. In 1984, Hunt was arrested for the killing of Ron Levin, an investor in the group, and later convicted of his slaying. The film dramatized the events.

Prosecutors in the 1993 trial tried to argue that the brothers took cues from the film. They even tried to have the made-for-TV movie played in the courtroom for the jury in an effort to show the similarities between the film and the murders of Jose and Kitty. However, the judge ruled against it.

In the new series, the brothers are seen writing a screenplay with their friend Craig Cignarelli, titled “Friends,” which depicts the son of a wealthy couple who kills his parents and commits more homicides. This was based on fact, as reported by the Los Angeles Times, and was one of two screenplays written by the brothers that became key evidence in the murder case.

Did the brothers spend lavishly after they killed their parents?

Yes. Reports state that the brothers went on a shopping spree, buying a Porsche, clothes and more, spending more than $700,000 in the months after their parents’ deaths. It was used as evidence against Lyle and Erik during their trial. The brothers stood to inherit $14 million from their parents’ estate, though over the years that dwindled because of taxes and legal fees.

Did they confess the murders to their therapist, Jerome Oziel?

Yes. In a Dec. 11, 1989, counseling session that Oziel recorded, the brothers confessed to killing their parents. The 2nd District Court of Appeal ruled in 1991 that the tapes were not subject to patient-therapist confidentiality and could be admitted as evidence. The tapes were subsequently played in the courtroom for jurors in 1993. In an article about that day at the trial, Los Angeles Times reporter Alan Abrahamson wrote how, in the tape, Lyle spoke about missing his parents, “and in a comment that set off gasps in the courtroom, Lyle Menendez added: ‘I miss not having my dog around. If I can make such a gross analogy.’ ”

How is Dunne connected to the brothers?

The journalist (and former film producer) wrote about the trials over the years, including an early article about the murders, “Nightmare on Elm Drive,” which is mentioned briefly in the series. Murphy said he and his team did years of research not just on the historical record, but also the many points of view and theories that surrounded the brothers and their crime.

Did a juror really have a heart attack during deliberations?

Yes. Her name was Leigh Valvo. She was the jury foreman in the 1996 trial. After Valvo suffered a heart attack, she was replaced by alternate juror Bruce Seitz, who reportedly persuaded jurors to give the brothers life sentences versus the death penalty.

Where are the brothers now and what has happened since their conviction?

The brothers were sentenced to life in prison without possibility for parole. As seen in the final moments of the last episode, the brothers were taken to separate prisons: Lyle was sent to the California Correctional Institution near Tehachapi, and Erik went to the California State Prison near Sacramento. However, after more than two decades apart, they were reunited at San Diego’s Richard J. Donovan Correctional Facility in 2018.

Erik and Lyle appealed multiple times in state and federal courts, but ultimately their convictions have been upheld. After the release of “Menendez + Menudo: Boys Betrayed,” the brothers filed a petition asking for their convictions to be vacated or for a new evidentiary hearing, although it could be an uphill battle. No decision has been made on the petition, and it’s unclear when there could be a ruling.