The Testaments is conveyed through three narrative points of view, with each character perspective highlighting specific themes: Aunt Lydia, one of the founders of Gilead; Agnes Jemima, a young woman raised under the Gilead regime; and Daisy, a young woman who was smuggled out of Gilead by the resistance during infancy.

Political Control of Women's Bodies and Reproductive Rights

Aunt Lydia's perspective frequently enters the past as she outlines the factors leading to the rise of Gilead. In response to drastic declines in fertility worldwide due to environmental toxins and chemicals, leaders of the Gilead regime took complete control of women's bodies. While Gilead's leaders preach the sacredness of feminine purity and the vital importance of reproduction, they treat women as subhuman. The few fertile women in society become "handmaids," forced to bear children for Gilead's elite. Abortion and the refusal to bear children are punishable by death. Handmaids are forced to procreate with their masters, and their children are raised by the masters and their wives.

Manipulation of Religion for Political Gain

The novel's epilogue takes place over a hundred years after the fall of Gilead, during which time historians consider its religion to have been Puritan. The religious elements of the regime are conveyed through the perspectives of Aunt Lydia and Daisy. Aunt Lydia's journal entries indicate the regime's indoctrination of girls and young women through the manipulation of the religious ideals of the Christian Bible. Female citizens of Gilead are not permitted to read the Bible, with the exception of the Aunts and women training to become Aunts. Having finally been granted permission to read the Bible, Agnes Gemima's perception of Gilead shifts. She realizes that Gilead's interpretations of the Bible do not reflect the Bible's actual contents or the God she has been taught to worship.

The Role of Espionage and Covert Operations

A surprising twist that develops in The Testaments is the fact that Aunt Lydia, portrayed in The Handmaid's Tale as an infamous villain, has secretly been aiding the resistance group known as May Day for decades. From inside Gilead, she passes information to May Day operatives in Canada through a secret message system communicated through microfilms. She is extraordinarily cunning in her manipulation of Commander Judd, acting as a faithful servant of the Gilead regime while corresponding with May Day and helping their operatives smuggle handmaids and their children out of the country. Aunt Lydia tells Commander Judd that she has helped return Baby Nicole (Daisy) to Gilead, when in reality, she has aided May Day's mission to send Daisy into Gilead as a spy. Daisy pretends to have been converted to the Gilead way of life and enters as a Pearl Girl, eventually returning to Canada to help destroy the regime.

Exposing Government Conspiracy and Hypocrisy

Lydia refers to the Aunts as the secret keepers of the regime, and over the years she comes to the understanding that Gilead's leaders represent the same corruption they claimed to eradicate after abolishing the United States democracy. Through her illegal journal entries, readers learn that she has secretly been collecting information on the crimes committed by Gilead's elite. For decades, the leaders of Gilead have made the Aunts responsible for covering up murder, infidelity, pedophilia, and other serious crimes. This information is eventually passed on to May Day and becomes critical to the fall of Gilead due to the turmoil that follows these revelations.