A speculative essay that asks whether girlhood the realm of playacting, hidden worlds, and secret identities - can be understood as a portal to alternate futures and queer possibility. At age five, K-Ming Chang imagines ghostworld into existence - an uncanny double of earthly reality accessible only to her and her best friend M. Like any intensely fantasized childhood game, ghostworld stretches the bounds of reality. It's hidden outside of time, held in place by the shared act of playing pretend. Later on, as an adult still drawn to the memory of this friendship, Chang returns to girlhood's 'field of play.' Girlhood, she posits, is itself a kind of ghostworld: a phase that ends when a girl dies so a woman can be born. But it is also the realm of playacting, hidden worlds and secret identities, intimate friendships with other girls. Its transience and frivolity offer space for queer possibility: girls may practice marrying each other, playing house, holding hands. In Ghostworld, Chang asks what potential lies in understanding girlhood not as a phase to be endured and discarded but as a means of disrupting normative adulthood. What happens when we reactivate girlhood's imaginative practices and the social worlds they generate? What can we cull from our childhood games? How can we make, of our girlhood selves, a present world of our own imagining? Ghostworld is part of the Undelivered Lectures series from Transit Books.