The Targum Pseudo-Jonathan on Exodus 11:5 announces the tenth plague in language that is almost merciless in its precision.
"Every firstborn in the land of Mizraim shall die: from the firstborn of Pharoh who should sit upon the throne of his kingdom, unto the firstborn son of the humblest mother in Mizraim who grindeth behind the mills, and all the firstborn of cattle."
The Aramaic paraphrase, preserved in the Targum attributed to Yonatan ben Uzziel, draws the social arc with care. At the top — bar Pharoh d'atid l'mita al kursei malchutei — the firstborn of Pharaoh, the one destined to sit on the royal throne. At the bottom — bar amtaha d'tachan batar rachaya — the firstborn of the lowest maidservant, the girl who grinds grain behind the mills.
This is the Torah's theology of judgment at its starkest. There will be no caste that escapes, because the crime was not one caste's alone. All of Egypt had participated in the enslavement of Israel — the prince who would inherit the system, and the maidservant who benefited, however meagerly, from the stolen labor. All would lose what they treasured most.
And — v'chol bechor b'ira — every firstborn of the cattle. Because Egypt's idolatry included animal deities. Even the sacred bulls and rams were not exempt.
The Maggid teaches: when the Holy One's judgment arrives, He does not target only the architects of the evil. He touches every level of a society that consented. This is terrifying — and it is also the reason the Seder begins with the words Avadim hayinu, "We were slaves." Because we remember what it cost Egypt to let us go. And we never want to become the empire that must be broken that way again.