It was a case that left people around the world baffled and investigators with more questions than answers.

What really happened to Denise Huskins?

On March 23, 2015, Huskins vanished from her home in California, which she shared with boyfriend Aaron Quinn, before mysteriously appearing two days later in her hometown.

Quinn called the police a day after she disappeared and claimed a man in a wetsuit armed with a Taser broke into their house, drugged him, forced his partner to tie him up and kidnapped her.

But two days later after a ransom for $11,000 was set, she showed up in Orange County unscathed and with an overnight bag in hand.

The case was described as a real-life Gone Girl, after the 2012 book by Gillian Flynn in which character Nick Dunne is suspected of being responsible for the disappearance of his wife, Amy.

Why police suspected a Gone Girl case

After Huskins re-emerged, police were left questioning whether a kidnapping had ever taken place.

Instead, they believed it was a hoax by the couple.

But what actually happened was so bizarre that it is now back in the spotlight thanks to a Netflix documentary American Nightmare, which premieres Wednesday.

When Quinn called police, he was asked to explain what happened on the night of Huskins’ disappearance. Authorities didn’t believe his story and instead suspected he was behind her disappearance.

Denise Huskins and Aaron Quinn on Monday, as their lawyers addressed a news conference in Vallejo, California. Photo / AP

It was revealed that Huskins had found messages on Quinn’s phone with his ex-fiancee that indicated they were planning to get back together.

The day before her short disappearance, Huskins went to Quinn’s home to discuss their relationship and whether it should end. Quinn’s ex had only recently moved out.

The couple went to bed before Quinn claimed they were woken at 3am.

He told police he heard a voice from an intruder saying, “This is a robbery.” He claimed the intruder then put Huskins in the boot of Quinn’s car before driving it away.

He said the assailants explained they would kidnap Huskins for 48 hours, during which time he had to complete tasks via email and phone, starting with calling in sick for both of them.

He said he was ordered to pay a ransom of US$8500 and that the kidnappers had installed a camera in his home so he couldn’t call police.

Eventually, he was able to contact the authorities, explaining that the assailants had snatched his girlfriend and drugged him.

Days later, Huskins returned home unscathed. Police said it was “such an incredible story, we initially had a hard time believing it, and upon further investigation, we couldn’t substantiate any of the things he [Quinn] was saying”.

They soon accused the couple of creating a hoax, despite the pair claiming their innocence.

At the time, police told a press conference: “Mr Quinn and Ms Huskins have plundered valuable resources away from our community and taken the focus away from the true victims of our community while instilling fear among our community members. So, if anything, it is Mr Quinn and Ms Huskins that owe this community an apology.”

When Denise Huskins reappeared after 48 hours, no one believed her story. Photo / AP

Twist in Huskins’ disappearance plot

Just as police became convinced the pair were guilty, a person claiming to be the kidnapper contacted the San Francisco Chronicle, saying they were annoyed at the hoax claims and sending images of where Huskins had been held.

A man was eventually caught in connection with the kidnapping, drugging and sexual assault of Huskins after he attempted another robbery and left his phone behind, which contained evidence.

It led police to the discovery that a man named Matthew Muller had kidnapped Huskins.

He was arrested three months later and pleaded guilty in 2016.

Matthew Muller was eventually identified as Denise Huskins' kidnapper. Photo / AP

Muller put blackened swim goggles on the couple and headphones over their ears, playing a recorded message that threatened he’d cut Huskins’ face or give her an electric shock if they didn’t comply, according to court documents.

At the time, Associated Press reported that Muller sent an email to a reporter with a recording of Huskins’ voice to prove she was alive.

Another email from Muller also had images of items used in the kidnapping.

He was eventually sentenced to 40 years in prison.

In court, a tearful Huskins told her kidnapper: “You treated me like an object, a toy, an animal.

“I still have nightmares every night. Sleep is not rest for me. It is a trigger.”

Neither her life nor Quinn’s has been the same since. She sued police after they claimed she was part of a hoax and won a $3.2 million settlement.

However, it took six years before the Vallejo Police Department formally apologised to Huskins.

She and Quinn are now married to each other.

‘When law enforcement decides the truth can’t possibly be true’

The case has now been made into a documentary series called American Nightmare.

Netflix’s promotional material says: “On March 23, 2015, Denise Huskins and her boyfriend Aaron Quinn were woken in the dead of night by a home invader.

“Huskins was kidnapped, and what transpired next in the terrifying, twisty (and twisted) tale is the subject of American Nightmare, the new docuseries from The Tinder Swindler filmmakers Felicity Morris and Bernadette Higgins.

“The story of Huskins’ disappearance invited national media scrutiny, with many comparing it to the 2012 Gillian Flynn novel Gone Girl. Law enforcement claimed the young couple’s recounting of the events was too far-fetched for anyone to believe.

“Incorporating a mix of interrogation footage and new interviews, the three-part docuseries unravels the consequences of our cultural rush to judgment – and what happens when law enforcement decides the truth can’t possibly be true.”