In a nursing home on the outskirts of Cork, an elderly nun lies dead. She has been suffocated. It looks like a mercy-killing - until another sister from the same convent is found viciously murdered, floating in the Glashaboy river. Why would anyone want to kill them? As she investigates, DS Katie Maguire discovers a fifty year old secret that just might lead her to the killer... if the killer doesn't find her first.