WHAT really happened to Australian backpacker Britt Lapthorne?

Sadly, we may never find out, but there are strong theories about the case.

Almost seven years since her disappearance from a Croatian nightclub, the investigation into the death of the 21-year-old will come to end.

The Victorian inquest into Ms Lapthorne’s death, who disappeared from a Croatian nightclub in 2008, will close on Thursday with little hope the answers to the mysterious circumstances surrounding the student’s death will be revealed.

The Australian reports Ms Lapthorne’s family “understands the investigation is virtually closed pending fresh information”.

Ms Lapthorne’s decomposing body was found by fisherman in Croatia’s Boninovo Bay almost three weeks after her disappearance, on September 18 2008.

She was last seen partying with a group of ten backpackers at the Latin Club Fuego in the coastal, tourist town of Dubrovnik.

At the time, the Lapthorne family were not told their daughter was missing for six days after she disappeared, despite Australian officials being aware she had vanished.

While Croatian police were never able to solve the mystery, Ms Lapthorne’s family believe she was a victim of homicide. They allege her killer attached weights to her body and proceeded to dump her into the Adriatic Sea.

In 2009, Ms Lapthorne’s father, Dale, said the only information he would release from one of the reports was that Britt’s body was in the water the whole time she was missing.

According to Mr Lapthorne, weights are the only possible explanation behind why his daughter’s body did not float to the surface.

At the time, the coroner confirmed Ms Lapthorne’s body should have surfaced within two or three days.

“It’s the reason for the rapid decomposition of her body,” Mr Lapthorne told AAP in 2009.

“We believe it’s highly likely somebody took her life,” he told The Australian.

“Britt was the sort of person that, had somebody attacked her, she would scream to let people know.”

An autopsy on Ms Lapthorne’s body was undertaken in Australia at the family’s request, with results suggesting she did not fall or jump from the high coastal cliffs where she likely died.

State Coroner Ian Gray will hear a summary of previously unreleased reports prepared by both the Australian Federal Police and Croatian authorities.

Then the coroner will prepare his finding, to be released at a later date.

While the criminal investigation remains open in Croatia, Ms Lapthorne’s family doesn’t hold out hope for answers.

Authorities where Ms Lapthorne died believe her cause of death was due to “misadventure”, but in 2013 conceded it was unlikely her death was a suicide.

Ms Lapthorne’s family have not received any communication from Australian Federal Police or Croatian police for “some time”, reports The Australian.

“We may never get the answers,” said Mr Lapthorne.

“Even if somebody was charged with her death, I’m not sure it would give us any satisfaction. The only thing we want is our daughter back, and that we know we can’t have.”