In a near-future Earth transformed by climate catastrophe, a Maryland ecologist is startled when a visitor from an interstellar network arrives with an urgent message: humanity must prove it can work together, or risk being left behind. Ruthanna Emrys’s A Half-Built Garden is a thoughtful, hopeful science fiction novel about first contact, environmental recovery, and the hard work of building a livable future in the midst of political and ecological upheaval.