The Science fiction genre has justifiably been accused of being dominated by masculine themes and male authors. However, starting in the 1970s women writers successfully began using its transgressive potential to explore gender and sexuality outside heteronormative and patriarchal power structures. In her 1998 novel Mission Child, Maureen F. McHugh builds on this tradition and takes it in a new direction as she sends her protagonist Janna/Jan on a journey to transcend not the regional borders of their home planet, but also those of the gender binary and its associated conventionalized gender expectations. In this paper, I will explore how Janna's multiple border crossings—along the intersections of gender, gender divergence, race, class—help to illustrate the predicament faced by the transgender community in the US today. In order to show this, I will take a close look at two episodes from the novel. Thus, this paper will explore questions such as: How can we reconcile that a person is, on the one hand, granted male-privilege on the basis of their gender presentation with the fact that the same person is in constant fear of being unmasked as an imposter and subject to gender discrimination in the form of gender misattribution. To explore these questions, this paper will employ the concept of intersectionality in conjunction with key theoretical concepts from transgender studies such as gender misattribution as a form of social domination. In the process, I will argue that Mission Child potentially enables its readers to contemplate power relations that transcend binary conceptions of identity and thus to subvert heteronormativity.