In 1996 Samantha Hall, a young mother of two, was brutally murdered and her body dumped in parkland near Noosa in the heart of Queensland's Sunshine Coast. Despite suspicions, evidence was thin until the police called in a forensic palynologist - a pollen specialist. Forensic palynology is the use of pollen and spores to help solve crimes. It is another investigative tool, like fingerprint analysis and DNA profiling which is increasingly used by police to solve crimes. Interwoven with the unfolding story of how Samantha's killer was brought to justice, A Grain of Truth opens the door on a new forensic tool that is being used to solve crimes and other mysteries.