After one particularly catastrophic day at their respective workplaces, busy professionals Maddie and Leo find themselves both unemployed. Dreaming of a fresh start but needing reliable income to support the family they hope to start together, the couple have a chance encounter with Kai, a smouldering kombucha artisan raking in the cash. Seeing dollar signs, Maddie and Leo swipe Kai's kombucha culture to kickstart their own enterprise, but when they mix in some mysterious herbs from a neighbour's garden, the culture gains sentience and proves deadly. With their relationship hanging by a thread, can Maddie and Leo unite to prevent a full-blown zombucha apocalypse?