Grace Pudel (Sarah Snook) is a lonely misfit with an affinity for collecting ornamental snails and an intense love for books. At a young age, when Grace is separated from her twin brother Gilbert (Kodi Smit-McPhee), she falls into a spiral of anxiety and angst. Despite a continued series of hardships, inspiration and hope emerge when she strikes up an enduring friendship with an elderly eccentric woman named Pinky (Jacki Weaver), who is full of grit and lust for life.