The film opens on the female lead, Sam, excitedly announcing that she is pregnant. Her long-term partner, the male protagonist, Guy, is overjoyed. However, over the subsequent nine months, Guy becomes increasingly isolated and detached from the world and from his ‘self’. He progressively develops an obsession with simulation theory, a physics theory which posits that the universe is nothing more than a computer simulation and that life only exists as a digital product. Meanwhile, as Sam gets closer and closer to childbirth, she struggles to balance the physical and emotional demands of pregnancy with those of an increasingly distant and alienating boyfriend.