Ay Mariposa tells a story of La Mariposa, Zulema, and Marianna–three characters in the Lower Rio Grande Valley of Texas whose lives are upended by plans to build a US-Mexico border wall. As the director of the National Butterfly Center, Marianna Trevino Wright has become a leader of wall resistance in the Valley, a position that has resulted in violent threats from pro-wall factions and an emotional odyssey as she tries to navigate the ever-shifting sands of border policy. Zulema Hernandez, a life-long migrant worker, immigrant and great grandmother, has been a dedicated advocate for all migrants, both wild and human-kind. Meanwhile the butterfly, La Mariposa, fights its own daily battle for survival in a landscape where more than 95 percent of its habitat is long gone and much of what remains lies directly in the path of the wall.