Ashraf Marwan, the son-in-law of former Egyptian president Gamal Abdel Nasser and a top aide to Nasser’s successor, Anwar Sadat, is depicted in a trailer for a coming Netflix film as one of “Israeli Intelligence’s most precious assets of the 20th century.”

“The Angel,” a thriller by Israeli director and screenwriter Ariel Vromen, appears to put a definitive stamp on Marwan’s enigmatic life as the spy who tipped Israel off to Egyptian and Syrian plans for a surprise attack on Yom Kippur 1973 and helped to avert an Israeli defeat.

“Why are you helping Israel?” a voice asks in the trailer.

“Because millions of innocent people will die, on both sides, that’s why!” the actor depicting Marwan answers urgently, his voice shaking.

But the truth, according to both Israeli and Egyptian writers, politicians and historians, is far more complicated and, ultimately, may never be known. Marwan died in 2007 in an apparent fall from the balcony of his London home in what appeared to be a suicide. No final ruling on the cause of death has been made, and his family has suggested he was murdered, adding to the intrigue over the 63-year-old’s life.

According to the Telegraph, in the months before his death, Marwan told his wife unnamed enemies were out to kill him, and a manuscript of his memoirs had been stolen from his home around the time he died.

After his unmasking as a possible intelligence asset for Israel’s Mossad in 2003, Egypt quickly claimed him as a cunningly effective double agent who was, in fact, duping Israel into costly mistakes ahead of the 1973 war.

His disputed status and sudden death briefly became fodder for theories exploring the shady sources of his wealth and his proximity to the top echelons of Egypt’s political elite. But Marwan’s story, and significance, faded as the 2011 popular revolt against longtime Egyptian President Hosni Mubarak erupted.

Netflix, which is popular in Egypt, has reignited the dormant debate — much to the chagrin of the nationalists dominating Egypt’s public life under President Abdel Fatah al-Sissi, who assumed power in 2014.

The film is “part of a concerted effort by Israel to make the Mossad look good and to continue to malign and slander Egyptian national symbols,” Egyptian lawmaker al-Husseiny Tag al-Din is quoted as saying in the newspaper al Watan.

The article says Mona, Marwan’s widow and the daughter of Nasser, declined to comment on the film’s trailer but has said in the past her husband worked for the interests of Egypt and anything said by Israel about him is baseless and bereft of any truth.

Egyptians on social media slammed the film and wondered whether their government would add Netflix to its growing list banned websites, which number in the hundreds. Some criticized the filmmakers' decision to cast an Israeli actor to play Sadat, while others said they are curious to see it and suggested it would probably be a closer portrayal of the truth than anything the Egyptian government has offered up.

Most, like a YouTube user called An Edgy Egyptian, dismissed it as “propaganda.”

“An incredibly one sided story,” the user commented under the trailer on YouTube.

While the Egyptian government has not provided a fuller narrative to back up the claim Marwan was deceiving Israel, Egyptians have pointed to vague instances of government recognition of his service.

Marwan’s funeral, at which his coffin was draped in an Egyptian flag, was presided over by the nation’s top imam and attended by Mubarak’s younger son and onetime heir apparent, Gamal Mubarak, along with Egypt’s powerful spy chief, Omar Suleiman.

After Marwan’s death, the elder Mubarak told state media that Marwan “carried out patriotic acts that it is not yet time to reveal.”

“The Angel” is based on a book by Israeli historian Uri Bar-Joseph, “The Angel: The Egyptian Spy Who Saved Israel” that portrays Marwan as an undeniable mole who provided Israeli intelligence with unimpeachable information on Egypt’s war plans. The 2016 book suggests he was possibly motivated by Nasser’s early distrust of him as both a son-in-law and aide.

Nasser allegedly only reluctantly agreed to Marwan marrying his daughter, seeing the young operative as more motivated by political ambition than love.

Still, after Nasser’s death in 1970, Marwan ascended to become a close aide to Sadat, putting him in proximity to the regime’s most closely held secrets. The film tracks his efforts to relay war plans to a dedicated Mossad handler and how they were used to counter Egypt and Syria’s attack.

According to author Howard Blum, who had spoken with Marwan before his death, the story is not quite so neat. Within Israel’s security apparatus, there was a fierce debate over Marwan’s loyalties despite a Mossad inquiry that concluded he was not a double agent.

Marwan had warned Israel that Egypt planned to attack in May 1973, provoking a massive deployment of troops and a heightened state of alert over a war that did not materialize — costing Israel millions of dollars and perhaps faith in “The Angel.”

When another warning from Marwan came on the eve of the October 1973 war, Israeli military officials were wary and ordered a significantly smaller mobilization that initially struggled to repel the Egyptian and Syrian attack.

For some Israeli military officials, Marwan’s initial head-fake in May was proof he was a double agent, Blum wrote.