Ay Mariposa tells a story of 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. Ay Mariposa documents each characters' fierce commitment to home, justice, wild beauty and the future of the US-Mexico borderlands.