Sheila Armstrong's second novel, The Red Mouth, is reviewed as a profound and exquisitely written exploration of Ireland's boglands and "deep time". The story centres on two discoveries made in an Irish bog – the antler of a great Irish elk and the mutilated body of a girl known as Belroe Woman – and follows the intersecting lives of characters haunted by these finds and the uncanny landscape that produced them, including a lonely returned émigré, an anxious scientist, a turf-cutter and an obsessive archaeologist.

The novel, which follows Armstrong's acclaimed 2023 debut Falling Animals, circles its characters across decades, tracing how troubled young daughters grow into troubled adults and how the bog itself shifts from managed wilderness into national park. The review praises Armstrong's lyrical prose, blending scientific terminology, Irish folklore and language, and highlights the book's meditation on the tension between ancient geological time and the urgency of the present, likening its style to Irish writers such as Paul Lynch and Sara Baume.