Marianne Faithfull, left, and Jim Morrison. (Photos by AP)

1971 wasn’t a banner year for Doors frontman Jim Morrison. Months after being convicted of indecent exposure for dropping his pants at a show in Miami, the once-svelte 27-year-old Lizard King moved to Paris, recorded widely loathed poetry and died in a bathtub.

ADV. FOR WKD. EDS, NOV. 28-30--FILE--Members of the Doors pose for an undated publicity photo. From left; John Densmore, Robbie Krieger, Ray Manzarek and Jim Morrison. Morrison died in 1971 at age 27. A four-CD boxed set of Doors material has been released, breaking sales records for boxed sets this year in its first week of release, according to Electra Records. (AP Photo/file) The Doors: from left, John Densmore, Robby Krieger, Ray Manzarek and Jim Morrison. (AP Photo/file)

Unfortunately for generations forced to listen to conspiracy theories spun by Doors keyboardist Ray Manzarek (RIP), what killed Morrison remains controversial. Doctors cited heart failure aggravated by heavy drinking — Morrison could reportedly polish off 36 beers in a day. However, because no foul play was suspected, French authorities skipped an autopsy.

Now, in an interview with England’s Mojo magazine, singer Marianne Faithfull says she knows who killed Morrison: her then-boyfriend, a heroin dealer named Jean de Breiteuil who inadvertently sent the singer on a final ride with Mr. Brownstone. Faithfull says when de Breiteuil went to visit Morrison for what would be the final time, she skipped the trip.

“I could intuitively feel trouble,” Faithfull told Mojo. “I thought, I’ll take a few Tuinal and I won’t be there. And he went to see Jim Morrison and killed him. I mean I’m sure it was an accident. Poor bastard. The smack was too strong? Yeah. And he died. And I didn’t know anything about this.”

Singer Marianne Faithfull, a major pop star in the 1960's, now a 55-year old grandmother, has released a new album titled "Kissin' Time" and is pictured in this undated publicity photograph. NO SALES REUTERS/Mary McCartney/Virgin Records/Handout FEATURE-LEISURE-FAITHFUL ORG XMIT: LOA18 Marianne Faithfull (Mary McCartney/Virgin Records via Reuters)

Faithfull, who will soon embark on a 50th anniversary tour, is a performer unfortunately pushed to the margins of rock history. She’s perhaps better known as Mick Jagger’s former girlfriend than the co-writer of the Rolling Stones classic “Sister Morphine.”

But who the heck is Jean de Breiteuil?

According to trashy rock biographies and limited news reports, a French aristocrat — that’s Count de Breiteuil — who liked drugs and rock stars.

“He was a horrible guy, someone who had crawled out from under a stone,” Faithfull wrote in a 2000 autobiography. She added: “What I liked about him was that he had one yellow eye and one green eye. And he had a lot of dope. It was all about drugs and sex.”

Even the spelling of his name is open to question — Mojo went with “Breiteuil,” so we are too. But other sources, including the unimpeachable Italian Wikipedia, use “Breteuil.”

When rumors about Morrison and heroin have flown before, Breiteuil, who was romantically linked with Morrison’s partner Pamela Courson, is often mentioned.

“‘De Breteuil was Pam’s dealer, and had supplied the heroin on the night,” said a nightclub manager who published a memoir in 2007. (The manager claimed Morrison died in a bathroom at his club, then was carried back to his apartment — a theory Faithfull isn’t selling.)

According to a 2004 Daily Mail article, Breiteuil also claimed to have sold Janis Joplin the heroin that killed her in 1970.

What’s agreed upon: Breiteuil died of an overdose in Tangier, Morocco, in 1971.

“Jean saw himself as dealer to the stars,” Faithfull wrote in 2000. “Now he was a small-time heroin dealer in big trouble. He was very young. Had he lived, he might have turned into a human being.”

Only Faithfull, 67, is left to tell — or, maybe, embellish — the 43-year-old tale about Morrison’s death.

“Everybody connected to the death of this poor guy is dead now,” she told Mojo. “Except me.”