The inquest into William Tyrrell's disappearance will focus on a completely new suspect.

Almost five years after the words were first uttered, Monday marks the beginning of a NSW coronial inquest focused on answering the question: where is William Tyrrell?

The inquest into the toddler’s disappearance in 2014 will focus on a new person of interest – one man who has never been at the centre of the investigation before or publicly discussed by detectives, The Sun-Herald and the Sunday Age report.

Despite NSW police continuing to conduct one of the state’s most intensive police investigations in recent history, no one has ever been charged in relation to the foster child’s case.

In September, 2014, three-and-a-half-year-old William was playing with his sister in the front yard of his foster grandmother’s house in Kendall, NSW, when he seemingly vanished into thin air. It was the beginning of the family’s nightmare.

Listen to The Quicky debrief on the truth about William Tyrrell’s parents, and what happened after the three-year-old’s disappearance.

Deputy State Coroner Harriet Graham’s inquest, beginning in Sydney on Monday March 25, will see multiple witnesses testify, from William’s foster parents, whose identities have been kept anonymous, and his biological mother Karlie Tyrrell, to representatives of NSW Police and the Department of Family and Community Services.

According to SBS, the inquest is expected to focus on the initial investigation, beginning with the 000 call made by William’s foster mother that afternoon, before looking into the toddler’s possible abduction.

Over the last four-and-a-half years, investigators have looked into 600 persons of interest, sifted through 15,000 pieces of information and conducted a four-week “forensic” search of the bushland surrounding William’s foster grandmother’s Kendall home, The Sydney Morning Herald reports.

In 2015, police also discovered an alleged north coast pedophile ring active in the area at the time of William’s disappearance. Sadly, none of these leads have led authorities to learning what happened to the toddler in the Spiderman suit, or if he is still alive today.

Hopefully, through the upcoming coronial inquest, investigators and William’s foster and biological families will come closer to uncovering what happened to William.