Prophet Muhammad has said that if every night Surah Al-Mulk is recited, then the reciter shall be protected from the tortures of the grave.
Prophet Muhammad was reported to be saying, "There is a Surah which will plead for its reciter till it causes him to enter paradise."
The name of this surah refers to Malik al Mulk, "The Owner of All Sovereignty", and literally "King of the realm," one of the 99 Names of Allah.
Surah will fight for you in the afterlife until the person enters heaven.