12 of Hollywood's Juiciest and Interesting Conspiracy Theories

In 2005, the conspiracy theory about Avril Lavigne being cloned after her alleged death started lurking on the internet. According to reports, the "Sk8r Boi" singer has been using a body double named Melissa after the real Avril died between the release of her albums Let Go and Under My Skin in 2002 and 2004, respectively.

Some of the alleged "evidence" included how Lavigne and Melissa's fashion choices differed, in addition some clues in her songs.

She addressed it in an interview with EW and called the theory a "dumb internet rumor."

"[I'm] flabbergasted that people bought into it. Isn't that so weird?" she said. "It's so dumb. And I look the exact same. On one hand, everyone is like, 'Oh my god, you look the same,' and on the other hand people are like, 'Oh my god, she died.'"

Ben Affleck and Matt Damon experienced a massive push in their careers when they worked together to write Good Will Hunting's script. On The Drew Barrymore Show, they shared how they were left broke six months after earning $600,000 from it.

Per the conspiracy theory, the script — which won them an Oscar for Best Original Screenplay — was not original since William Goldman allegedly created it. The late novelist responded to the claims before his death and denied his involvement in creating the script.

Amid Beyoncé's success, she has dealt with a wild conspiracy theory about her getting pregnant with Solange Knowles as a teenager. It asserted the "Crazy in Love" singer is seven years older than her "younger sister," or she pushed back her age and was actually born in 1974.

After doing the math, the rumors suggested she got pregnant with Solange when she was about 12 or 13.

"Beyoncé's precise birthdate is 9/4/1974," the post which stirred the theory suggested. "I saw a picture of her driver's license that was on my manager's computer once don't ask how. Beyoncé and Solange are both teenage mothers, I do not know the paternity of Solange."

Mark David Champman killed John Lennon on December 8, 1980, by shooting him at a close range outside his Upper West Side apartment building, and The Beatles member died a few hours later.

Despite the confirmation of the tragic loss, a bizarre conspiracy theory took the spotlight after seeing Lennon's lookalike Mark Staycer. According to the theorists, the performer is Lennon himself since the famed musician did not die decades ago.

Conspiracy theorists dragged Katy Perry to the spotlight and claimed that her lyrics, music videos and online posts are proof she is JonBenét Ramsey.

Ramsey was only six years old when she was struck on the head and strangled to death in their home. The yet-to-be-solved murder case went viral following the brutal killings of University of Idaho students, and the "California Gurls" singer responded to the story when Billy Eichner asked her to blink twice if she was really the late beauty queen.

"Um wait, no, that is not real," Perry answered.

Now 59, Keanu Reeves still deals with the conspiracy theory about him being immortal.

Dr. Richard Hames explained to Yahoo News' Conspiracies Unpacked that Reeves has lived in multiple identities for a long time, with Charles the Great as the first sighting. The John Wick actor reportedly lived as actor Paul Mounet, as well.

"[His] body, I don't think, was ever found, although there was some conjecture that he died of a heart condition," Dr. Hames continued.

Reeves seemingly added more fuel to the fire when he refused to deny the claims, telling Jimmy Fallon, "We're all stardust baby" when asked about his alleged disguises.

The official documents of Marilyn Monroe's death ruled a probable suicide caused by a barbiturate overdose as her cause of death — but theories claimed she was either killed by the Kennedys or a mafia.

Aliens were also linked to her death.

In 1981, Natalie Wood went missing while on a yacht following a dinner on Catalina Island. Her body was found floating after the Coast Guard, private searchers and Harbor Patrol combed the water and coastline near where she was last seen.

Los Angeles coroner Thomas Noguchi said in his report that "numerous bruises to arms and legs" were spotted, which Wood "probably sustained at the time of drowning." The document stated no other trauma or foul play was suspected.

Decades after the incident, tales that she was murdered continue tickling people's minds as they point fingers at Wood's husband, Robert Wagner.

Nicholas Cage set the record straight about him being a vampire who "reinvents himself ever 75 years."

The conspiracy theory claimed he looked ageless since he starred in Moonstruck. But in his interview with David Letterman, the Ghost Rider: Spirit of Vengeance reiterated no one can take pictures of vampires, so there would be no way he is the man in the viral photo who has a striking resemblance to him.

"Now look, I don't drink blood and the last time I looked in the mirror I had a reflection," Cage said.

Paul McCartney died in a car crash in November 1966 — at least that is what the "Paul is dead" theory had suggested for decades. The Beatles reportedly had no choice but to replace him with a Paul McCartney look-alike to save their fans from heartbreak.

He responded to the hoax story and declared he was not dead. He also based his 1993 live album Paul Is Live on the bizarre theory.

Paul Walker's death became a subject of countless theories after he was killed in a fiery car crash. Conspiracy theories suggested that the actor was murdered for discovering the inside information regarding the relief efforts for the victims of Typhoon Haiyan in the Philippines.

"They [Walker and a friend] discovered a conspiracy to supply victims of Typhon Haiyan with a prototype permanent birth control drug hidden in medicinal supplies and food aid," the theory claimed. "They had a d-------- recording and they were on their way to rendezvous with an ally who would have helped them get in touch with the right people."

It continued, "Turns out they were betrayed and someone rigged their car's breaks to malfunction after a certain speed."

Another version of the theory alleged Walker discovered dirty money in the disaster relief.

Online sleuths reportedly found clues that Britney Spears' online videos and images have been edited to hide the fact she has been missing. Others said people around the "Toxic" singer edited her voice to make it look like she was doing well.

The theory reemerged after Paris Hilton shared a photo of herself and Spears with their celebrity friends Emma Roberts, Drew Barrymore and Tiffany Haddish. The socialite immediately responded to the followers' comments about the "Everytime" crooner and called the conspiracy theories "absolutely ridiculuous."

"To all of those asking. Some of these photos were taken on an iPhone so they ended up being blurry," she explained. "So they used this app called Remini to make it look unblurry and sometimes the Ai distorts images."