Jarlath "Jar" Costello's girlfriend, Rosa, committed suicide when they were both students at Cambridge. Jar is obsessed with the idea that Rosa is still alive and is tormented by disturbingly real sightings of her.
When a startling discovery convinces him more than ever that these are not just hallucinations, Jar is thrust into the heart of a larger intrigue that may finally shed some light on Rosa's death.
