One-time Hollywood tough guy Gianni Russo is making waves again—this time off the screen.

In his newly released memoir, Russo drops the staggering claim that Pope John Paul I was murdered by the mob after just 33 days in office due to his efforts to halt a money-laundering operation involving the Vatican Bank, as New York Post reports.

Russo, 81, best known for playing the treacherous Carlo Rizzi in “The Godfather,” lays out his allegations in Mafia Secrets: Untold Tales from the Hollywood Godfather, penned alongside author Michael Benson and published by Citadel.

Alleged Power Struggle Inside the Vatican

According to Russo, the brief papacy of Pope John Paul I ended not from natural causes as officially reported, but from a deliberate and undetectable injection intended to stop his interference with illicit Vatican Bank transactions.

“He was taken out, given a hot shot of an untraceable drug, because he wouldn’t play ball,” Russo told The Post, claiming the late pontiff paid the ultimate price for pushing back against entrenched financial corruption.

The allegations center around then-Archbishop Paul Marcinkus, nicknamed “The Gorilla,” who was reportedly at the helm of the laundering scheme filtering mob money from Las Vegas into Rome.

Russo Says He Was Personal Courier for Mob Cash

Russo claims he played an unexpected role in this covert operation, transporting cash skimmed from casino revenues directly to Vatican City, acting on orders from infamous Chicago boss Tony Accardo.

These money drops allegedly ended once Pope John Paul I learned of the transfers and moved to shut them down, a decision Russo claims sealed the pope’s fate with the organized crime world.

“He crossed the mob and had to go,” Russo said bluntly, suggesting divine ordination was no shield against the darker elements of global power.

Old Scandal Resurfaces Amid Religious Allegations

While the Vatican has long denied wrongdoing in relation to the Banco Ambrosiano scandal that erupted in the 1980s, it did agree to a $250 million payment to creditors, and Marcinkus ultimately relied on diplomatic immunity to dodge prosecution before he died in 2006.

Russo says a former Swiss Guard confided to him the details of the so-called “untraceable” drug injection that brought the pope’s reign to an abrupt and suspicious end.

For many, this isn’t just a story about one actor’s colorful past—it’s also a disturbing reminder of how financial rot can creep into even the holiest of institutions.

Monroe, the Kennedys, and Mob Intrigue

The memoir doesn’t stop at the Vatican. Russo also claims a “non-sexual but intimate” bond with Marilyn Monroe that began in 1959 when he was just 16, and washing her hair at a beauty salon.

According to him, their connection deepened through the years, culminating in tense moments when Monroe allegedly revealed she was being exploited by the Kennedy brothers and had been pressured into an abortion by Bobby Kennedy.

“These Kennedy brothers. I am done with them. They’re using me like a piece of meat!” Russo quotes Monroe as saying, painting a dark undercurrent to the Camelot mythology often celebrated by media elites.

A Timeline of Dangerous Encounters

Russo recounts being instructed by mobster Frank Costello to steer clear of Monroe one weekend in 1962—a move Russo claims was because of a blackmail scheme involving a hidden film camera at Lake Tahoe.

He claims Costello grew alarmed after learning Monroe had voiced the word “abortion,” leading him to grimly state, “They’re going to kill her.”

From there, Russo’s alleged journey took him into even darker territory, including encounters with Lee Harvey Oswald in New Orleans just before JFK’s assassination, under the watch of mob boss Carlos Marcello.

From Sinatra’s Glance to Pablo’s Jungle

Russo brags about witnessing the executions of Tony and Michael Spilotro, seeking help from John Gotti (who laughed him off), and being shipped off to Colombia, landing at the bizarre estate of drug kingpin Pablo Escobar.

He describes seeing Escobar beat hippos with a stick and jokes that “the more I learned about my host, the crazier he sounded.”

Despite decades brushing shoulders with crime lords and celebs, Russo maintains he was never officially “made,” claiming instead, “I am a made man—only by God.”

Publicity, Provocation, or Partial Truth?

Though Russo readily admits his stories sound sensational, few have been definitively corroborated. Still, the sheer volume of overlap between his alleged adventures and 20th-century turning points has piqued public curiosity.

He says he no longer fears fallout from the stories he’s telling. “Everybody’s dead,” Russo shrugs.

If even a fraction of this tale holds water, Russo's life may read less like a memoir and more like a roadmap of America’s shadow history—from mob hits to presidential pillow talk to Vatican cover-ups.