Some time in the summer, a small theater in Los Angeles screened a movie to which hardly anyone came.

It was a clunky film filled with scenes in a desert and in tents. The characters were cartoonish; the dialogue gauche.

The actors who'd responded to a July 2011 casting call thought they were making an adventure film set 2,000 years ago called "Desert Warrior." That's how Backstage magazine and other acting publications described it.

The American-made movie, it turns out, was hardly an innocent desert action flick.

Instead, the movie, backed by hardcore anti-Islam groups in the United States, is a tome on Islam as fraud. In trailers posted on YouTube in July, viewers saw this: scene after scene of the Prophet Mohammed portrayed as a womanizer, buffoon, ruthless killer and child molester.

Islam forbids all depictions of Mohammed, let alone insulting ones.

The Muslim world erupted in rage.

Protesters aired their anti-American anger in Egypt, Yemen, Tunisia, Morocco, Sudan, Iran, Iraq, Israel and the Palestinian territories. Violent mobs attacked the U.S. Consulate in the Libyan city of Benghazi leaving the ambassador and three other Americans dead.

As outrage spread, the film's origins still remained murky. Whose idea was it? Who financed it?

At the heart of the mystery was the filmmaker himself, a man identified in the casting call as Sam Bassiel, on the call sheet as Sam Bassil and reported at first by news outlets as Sam Bacile.

But federal officials consider that man to be Nakoula Basseley Nakoula, who was convicted in 2009 of bank fraud.

The FBI contacted the filmmaker because of the potential for threats, a federal law enforcement official told CNN Thursday. But he is not under investigation.

With media parked at his residence in Cerritos, California, Nakoula called the Los Angeles County Sheriff's Department Wednesday night to report a disturbance, said spokesman Steve Whitmore. He wanted local police to protect him.

When news of his movie first broke, the filmmaker identified himself as Sam Bacile and told the Wall Street Journal that he was a 52-year-old Israeli-American real estate developer from California. He said Jewish donors had financed his film.

But Israel's Foreign Ministry said there was no record of a Sam Bacile with Israeli citizenship.

"This guy is totally anonymous. At this point, no one can confirm he holds Israeli citizenship, and even if he did we are not involved," ministry spokesman Yigal Palmor said.

A search by CNN of public records related to Bacile came up empty. A search of entertainment records turned up no previous mention of a Sam Bacile, and the directors and writers guilds had no listing for him.

CNN has not been able to speak with the filmmaker.

A production staff member who worked on the film in its initial stages told CNN that an entirely different name was filed on the paperwork for the Screen Actors Guild: Abenob Nakoula Bassely. A public records search showed an Abanob B. Nakoula residing at the same address as Nakoula Basseley Nakoula.

He believed the filmmaker was a Coptic Christian and when the two spoke on the phone during production, the filmmaker said he was in Alexandria, Egypt, raising money for the film. There has been a long history of animosity between Muslims and the minority Copts in Egypt.