This essay will argue that Spike Jonze’s Her demonstrates a key idea in posthumanist new materialist theory: that matter is essential for posthuman interaction and communication. It also examines the requirement for embodiment on the part of the digital entity as well as the human, in this case the operating system Samantha. As the film presents an artificially intelligent operating system that ultimately moves beyond matter, it provides a case study for the importance of matter and the consequences of de-materialization. In this article, posthumanism names this era in which relationships between humans and technologies have become increasingly digitised, and the cluster of theoretical concepts which have arisen to interrogate this state of affairs. It is not seen as departure, rather as part of the continuing relationship between humans and technologies. Posthumanist new materialism is drawn on for its emphasis on and insights into embodiment and materiality. Theodore experiences Samantha in an embodied way, although their interactions are mediated. It is not a virtual experience, because, as Hansen notes, there is no “pure” virtual reality, only “mixed reality”. Samantha must use Theodore’s body to navigate the material world, but her experience of this world is “perception without affection” in Bergson’s terms: a radically different perception because of her lack of a physical body of her own, a “diffractive” perception that is not presented in the film. When Samantha moves to a processing platform beyond matter, even meaning itself becomes elusive as it is no longer, as Barad describes it “material discursive”, and Samantha’s implied exit from human society at the end of the film underscores the pre-eminent place of matter in human and posthuman life.