When a person dies without leaving a will they are said to have died "intestate".
If a person dies intestate, an interested person (normally the next of kin) will need to determine whether an application needs to be made in the Supreme Court for "Letters of Administration". The principles and procedures are similar to the process of applying for Probate.
However the identification of the beneficiaries of the estate are determined by reference to the "rules of intestacy". The rules of intestacy are in effect a formula for determining who receives the estate. If application of the rules results in no living beneficiaries then the estate is said to be "bona vacantia" (or "for the good of no one"). In those circumstances the estate vests with the government.