At about midday on September 16, 2008, Hannah Upp was floating face down in water in southern Manhattan, New York. Two men, who worked on the ferry deck nearby and were directed to rescue the woman after she was spotted by a captain, hoisted her up as she heaved for air.

Had they spotted her just minutes later, it could have been a very different story.

She was alive, but needed hospitalisation due to suffering from hypothermia, dehydration and severe sunburn on one side of her body.

Hannah Upp had been missing for three weeks.

“Teacher, 23, disappears into thin air,” one headline from Daily News read on September 5, 2008 – 11 days before she was eventually found.

In late August, the 23-year-old school teacher had left her New York City apartment to go for a run. When she was rescued from the waters, she said going for a jog was the last thing she remembered. While in hospital, it took time for her to reconcile with the fact that 20 days had passed since then. She simply had no memory of it.

“It was as if the city had simply opened wide and swallowed her whole,” the New York Times wrote about her 2008 disappearance.

One night, while she laid asleep in the hospital with her mother by her side, she abruptly awoke and said “I was at a lighthouse,” according to The New Yorker. But when her mother, Barbara, asked Hannah about the lighthouse the next morning, she had no recollection.

“I went from going for a run to being in the ambulance,” Hannah said in an interview with the New York Times five months after her disappearance. “It was like 10 minutes had passed. But it was almost three weeks.”

Whilst in hospital, she was diagnosed with dissociative fugue.

Dissociative fugue is described by Psychology Today as a “psychological state in which a person loses awareness of their identity or other important autobiographical information and also engages in some form of unexpected travel".

It is characterised by sudden travel and a failure to recall the past. The illness tends to be precipitated by trauma – though Hannah could not recall any traumatic event in her past.

"It’s weird," Hannah later said in the interview with the New York Times. "How do you feel guilty for something you didn’t even know you did? It’s not your fault, but it’s still somehow you. So it’s definitely made me reconsider everything. Who was I before? Who was I then - is that part of me? Who am I now?"

After this first episode, Hannah managed to go on with her life seemingly as normal.

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Five years would go by before Hannah suffered her second episode of the rare amnesia disorder.

In September 2013, Hannah was working as an assistant teacher at a Montessori school in Maryland.

One morning, her mother was informed by police that her daughter’s wallet and phone had been found on a footpath. She was missing for two days when she regained her memory while in a creek in Maryland with a shopping trolley next to her, according to local reports from the time. She asked a stranger to borrow their phone, so she could call her mum, who came to retrieve her then 28-year-old daughter.

"Last night our beloved Hannah was located safe and sound and is at home. We are inexpressibly relieved and rejoicing. We are tremendously grateful for your thoughts and prayers and attentiveness during the time she was missing," Hannah's mum said in a public statement.

A year later, Hannah moved to St Thomas of the U.S. Virgin Islands in the Caribbean, where she also worked as a teacher.

Hannah was living on the island when Hurricane Irma surged through the Caribbean in September 2017 and caused devastating damage to her new home. She survived the hurricane, but was about to be hit by a second one within days.

On September 14, Hannah told her housemates she was going to school, but she never arrived, nor came home. The following day, her neatly-folded clothes and car keys were found at a nearby beach. It was the same month as her previous disappearances, and again, her disappearance was connected to water.

Her friends explored the shore and sea for three days, before they needed to suspend the search because another natural disaster was heading their way: Hurricane Maria.

In September 2017, amid her disappearance, her friends and family set up a Facebook page, Find Hannah Upp.

"If any one sees Hannah, please go to her," they wrote in a Facebook post on September 20, 2017. "She has a rare dissociative amnesia disorder that may be in play. If so, she may not know where she is, or who she is."

One of Hannah's friends, Jake Bradley, who is also an emergency medical technician, told The Virgin Islands Daily News on September 26, that: "We’ve done all the physical searching that I think we can do, other than having her posters put up everywhere.

"That’s going to be the only way, hopefully, if she sees one of them, if she’s in her fugue state, it would at least get her to the point where she realises something’s wrong and she goes to get help. That’s what we’re hoping for."

In the year after her disappearance, a GoFundMe page was set up to continue the search for Hannah.

"We have no way of knowing the length of time Hannah’s condition and journey may fill," the page, initiated by her mother and supported by friends and family, reads. "We are in this for the long haul."

Today, Hannah Upp remains missing. In September this year, it will be three years since Hannah was last seen and 12 years since her first fugue.

Her disappearance was the subject of the 2019 documentary, Vanished in Paradise: The Untold Story.

In their announcement of their involvement in the documentary, Hannah's parents wrote: "If Hannah is still out there somewhere, we never know what unexpected connection may lead us to a clue to locating her again. All it would take is for one person to see the program and recognise her...

"The circle of friends and family who miss her is still wide and strong, and each link matters.

"We take hope from the connections that continue and all who join us in reaching out to find Hannah."

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