The zombie apocalypse only affects anyone with high testosterone. As the male population turns into mindless grunts (insert predictable joke here), two trans women & a lone badass trans man who was off T at the time of the apocalypse (for top surgery) have to survive not just zombies, but hunt them as a source of estrogen (the fact that testicles contain estrogen and how to stir fry them is not a lesson I wanted to learn).

But the zombies are not the scary villains of the piece. Rather, it is the rampaging neo-fascist TERF state that seeks to execute anyone who doesn’t pass a genital inspection. I mean, they name their ship the Galbraith and use XX as their symbol so... They blame men for the end of the world and are more than happy to include trans women in that bracket of death. 

The thing is, testosterone is not the simple gender marker they believe it to be. Conditions causing a flare-up in testosterone, and hormonal changes during childbirth, lead to disastrous results requiring hunters such as the protagonists to bring back estrogen for the whole community; it’s not just trans women dependent on it but many cis women too. Not that it matters when it comes to firing squads.

Also, find out what happened to Rowling when the zombies struck.