Hi,I lost a book 10 years or so ago and I've desparately been trying to remember what it was ever since. It was by an Irish author,and was kind of a modern story with a fairy/folk tale twist. The main character had either not been to Ireland before,or had returned for the first time in a long time,I'm not sure It had "faeries" (not fairies,I remember that detail),who were weak to iron,a puca (Irish mythological creature) called Sam who betrays the main character,and a sacrificial ritual. It also had a headless monster who lives in the woods. I know that summary is kind of all over the place,but any help at all would be appreciated. Thank you!