Twelve years after 18-year-old Natalee Holloway vanished without a trace during a trip to Aruba, the unsolved mystery still captures national attention. Her father, Dave Holloway, planned to reveal new leads in the case during a television special titled "The Disappearance of Natalee Holloway," set to air Saturday at 7 p.m. EST on the Oxygen network.

Here's everything we know so far about the case before the special airs.

  • Holloway, an Alabama native, disappeared in May 2005 during a trip with her classmates to celebrate their graduation. The students planned to gather in the hotel lobby in the morning to meet before departing for the United States, but Holloway never showed up.
  • Though Holloway was officially declared dead in 2012 by Alabama judge Alan King, her body was never found.
  • Holloway was reportedly last seen with a 17-year-old Dutch man named Joran van der Sloot in the early hours of the last night of her trip. Witnesses said they saw her get into a car with van der Sloot and two Surinamese brothers named Deepak and Satish Kalpoe at about 1 a.m.
  • Van der Sloot was arrested twice after police suspected he had a hand in Holloway's disappearance but was let go shortly after for a lack of evidence. He denied any involvement. The Kalpoe brothers were each arrested three times, but also released on a lack of evidence.
  • Aruban prosecutors officially closed the case in 2007 without charging anyone. They reopened it within the year after van der Sloot said in a video that Holloway was dead and that his friend got rid of her body — a confession he later denied. Instead, he told the Dutch newspaper De Telegraaf that he sold Holloway into slavery.
  • Five years to the day after Holloway disappeared, a young business student named Stephany Flores was murdered in Peru. Van der Sloot subsequently confessed to the crime. Reports said Flores, 21, had found files relating to Holloway on van der Sloot's computer.
  • Van der Sloot was sentenced to 28 years behind bars in Peru for Flores' death. He remained, to this day, the primary suspect in Holloway's disappearance, though he was never charged.
  • Authorities in the United States said they planned to extradite van der Sloot as soon as he was finished serving his sentence.
  • Years later, an unidentified informant put Holloway's father in touch with a person who said they had intimate knowledge of her death involving van der Sloot. "We have a person who states he was directly involved with Joran van Sloot in disposing of Natalee's remains," Dave Holloway told "Today" this week.
  • Alongside a private investigator, Dave Holloway conducted an 18-month investigation into the leads given to him. During the investigation, they discovered a set of human remains in an undisclosed location in Aruba.
  • The human remains were sent for DNA testing to determine whether they might be Holloway's. Dave Holloway called the findings the "most credible lead" in the case yet.
Joran van der Sloot, shown here during a hearing in Lima, Jan. 13, 2012, remains the primary suspect in Natalee Holloway's disappearance. Getty Images