While I had suspicions this book was one in a series, I wouldn't have expected it to be the 12th in that series. The book focuses on Julia, an elderly lady admitted with a heart attack who sees a man covered with bruises in the emergency room bay next to hers. When that man is later found dead in a bathroom, Julia appears to have been the only person to see him in the ER while still alive, which is key when it is determined the man was murdered, and not by whomever or whatever inflicted those bruises on him. Julia is more than willing to talk to the police, but after doing so, she finds that her life might be threatened by more than just a faulty ticker.
I was obviously not familiar with the series before this book, nor its protagonist, Julia's college professor niece Sarah, or Sarah's husband, Alex, who is a physician. The writing was OK, but not spectacular, and the story was decent, but relied heavily on coincidence to keep the character pool small. I figured out part of the mystery pretty early but stuck with it to see how it all unraveled. I would consider reading another book in the series if it was medically-oriented, but don't think I would deliberately seek one out.