When the Postmaster of Inis Mór’s wife goes missing, the local Garda Síochána are baffled, and after searching the island for days with no success, Detectives from Galway are called in to help with the investigation.
When the detectives arrive, they discover a bloodstained knife and broken glass in the Postmaster's living quarters, and decide that she was killed and her body disposed of by the Postmaster, who is then arrested and charged.
But they believe that Tim O'Sullivan, the Postmaster, did not act alone and suspect that Conor O'Rourke may have been involved in her disappearance also. Conor travels to Dublin in a desperate attempt to protect both Tim the Postmaster and himself.