"You have to kill him." Imprisoned in the heart of a secret military base, Em has nothing except the voice of the boy in the cell next door and the list of instructions she finds taped inside the drain.Only Em can complete the final instruction. She's tried everything to prevent the creation of a time machine that will tear the world apart. She holds the proof: a list she has never seen before, written in her own hand. Each failed attempt in the past has led her to the same terrible present-imprisoned and tortured by a sadistic man called the doctor while war rages outside. Marina has loved her best friend James since they were children. A gorgeous, introverted science prodigy from one of America's most famous families, James finally seems to be seeing Marina in a new way, too. But on one disastrous night, James's life crumbles apart, and with it, Marina's hopes for their future. Marina will protect James, no matter what. Even if it means opening her eyes to a truth so terrible that she may not survive it. At least not as the girl she once was. Em and Marina are in a race against time that only one of them can win. All Our Yesterdays is a wrenching, brilliantly plotted story of fierce love, unthinkable sacrifice, and the infinite implications of our every choice. *"Time travel done right.Narrator Em and her boyfriend, Finn, escape from their totalitarian future, time traveling back four years to commit a heart-wrenching assassination of a loved one in order to prevent time travel from being invented and the future from turning so wrong. The future's hinted-at horrors are threatening but expertly backgrounded, avoiding dystopia-fatigue. The clever, accessible time-space treatment isn't weighed down by jargon. Em and Finn's proactive mission means the characters are the hunters instead of the frequently seen on-the-run teen protagonists. The other side of the storyline, taking place in the past that Em and Finn travel to and starring their past selves, is narrated by Marina (Em, in this timeline) and involves her brilliant yet interpersonally challenged best friend (and crush) James and his friend Finn, who annoys Marina, as they deal with a tragedy in James's family. The believable, complex relationships among the three characters of each respective time and in the blended area of shared time add a surprise: A plot ostensibly about assassination is rooted firmly in different shades of love. Perhaps richest is the affection Em feels for Marina-a standout compared to the truckloads of books about girls who only learn to appreciate themselves through their love interests' eyes.Powerful emotional relationships and tight plotting in this debut mark Terrill as an author to watch." --Kirkus, starred review