In a series of non-linear flashbacks, a linguist recounts her interactions with alien heptapods and the way learning their language changed her perception of time.
The linguist, working with a racist, is tasked with trying to understand the visitors' language which operates on a completely different, nonlinear semantic system. As she becomes more adept at understanding it, she starts to experience time the way the heptapods do - simultaneously and non-sequentially. She sees the past, present, and future all at once.
Your father is about to ask me the question. This is the most important moment in our lives, and I want to pay attention, note every detail.
The linchpin of the narrative is the narrator's reminiscence of her daughter’s life: birth, childhood and tragic early death in an accident. This nonlinear experience of time and the linguistic changes that it brings up were triggered by a question from her partner and the father of her child.
Telling it to you any earlier wouldn't do any good; for most of your life you won't sit still to hear such a romantic—you'd say sappy—story.
The story ends with the aliens leaving earth, the purpose for their visit remaining a mystery. The linguist is left forever transformed by the experience.