William Douglas, a long-time friend of Logan, travels to the Mackenzie lands to help. He brings along Amy , the clan’s healer, and her husband Aidan .
Margaret, the wife of Laird Logan Mackenzie, has died under mysterious circumstances. Logan is driven to near-madness by her death and is being kept locked away by his second-in-command, Graham.
Upon arrival, they realize the situation is much darker than they thought. The death of Margaret may not have been accidental, and there are layers of betrayal within the castle.
While Aidan and Amy are already a settled married couple, the book also explores a developing romance between Logan and a character named Shena. Reader Reception
AIDAN & AMY: Asesinato en el Castillo: Los Escoceses ... - Amazon.es
It sounds like you are looking for a blog post or summary about the book (Murder in the Castle) by Margotte Channing . While you mentioned "Ian," the characters in this specific series are actually Aidan and Amy .