Tuck is slow to understand the circumstances that have driven her family to an uninhabited island. She must care for her spirited young daughter and she lives moment-by-moment through the absurdity, beauty, paranoia, and hunger that shoots through her life, as her husband struggles to detox. Lungfish tells the story of a woman grappling through the lies she has been told - and those she has told herself to arrive at the truth of who she is.