This is one of my favourite shows on detectives. The caste is superb and the plot is amzing. Currently they are on the season 9 and it just keeps getting better and better.
If you are new to the whole idea, castle is an American sitcom about a detective Kate beckette and novalist richard castle and they solve crime cases together.
The season 9 opened with kate getting kidnapped and shot and the story is a nail bitter. I m just waiting for the next episode to be aired soon. If you love detective serials then this is the one. it has all the elements of suspense, thriller, romance and drama. Would totally recommend.