I seek justice, I finally said. I seek justice for my sister . . . Sometimes it takes twenty-nine years to say it out loud, to say it out loud on a phone call with a lawyer at the General Attorney's office: I seek justice.

On the dawn of 16 July 1990, Liliana Rivera Garza, Cristina Rivera Garza's sister, was murdered by her ex-boyfriend and subsumed into Mexico's dark and relentless history of femicide.

She was a twenty-year-old architecture student who had been trying for years to end her relationship with a high school boyfriend who insisted on not letting her go. A few weeks before the tragedy, Liliana made a definitive decision: at the height of her winter she had discovered that, as Albert Camus had said, there was an invincible summer in her. She would leave him behind. She would start a new life. She would do a master's degree and a doctorate; she would travel to London. But his decision was that she would not have a life without him.

Returning to Mexico after decades of living in the United States, Cristina Rivera Garza collects and curates evidence – handwritten letters, police reports, school notebooks, voice recordings and architectural blueprints – to defy a pattern of increasingly normalised, gendered violence and understand the life lost. What she finds is Liliana: her sister's voice crossing time and, like that of so many disappeared and outraged women in Mexico, demanding justice.