River and Ira investigate the murder of kebab shop worker Haider Jamal Abdi in a public library. They focus on both a cleaner, who was captured on CCTV but who does not appear on the books of the library's cleaning contractor, as well as on the lawyer who represented Haider at an immigration tribunal. Their findings lead them to a possible understanding of what Stevie herself may have been investigating and which might have led to her death.