Taking its primary name from its opening word—The Inevitable Reality—this revelation arrived in Makkah during the fifth year of Prophethood, shortly before the migration to Abyssinia. Sent to answer those mocking the Quran, it is also known as Sūrat al-Silsilah (The Chain), referring to the punishment awaiting deniers.

The narrative opens by establishing the terrifying certainty of the Resurrection, moving swiftly to the historical destruction of Thāmūd, ʿĀd, and the people of Pharaoh. After citing these ruined nations as proof of Allah’s power, it reminds humanity of their survival during Nūḥ's Flood. The sequence then turns to the final reckoning, contrasting the joy of those handed their records with the despair of the seized and chained.

The text closes with a vigorous defense of the Prophet (ﷺ) against accusations of poetry and soothsaying, fiercely affirming the revelation is free of forgery. It was these exact verses that ʿUmar ibn al-Khaṭṭāb overheard the Prophet (ﷺ) reciting in Makkah, and their refutation of poetry caused Islam to enter his heart.