Castle follows Richard Castle, a famous mystery novelist who has writer's block. He is brought in by the NYPD for questioning regarding a copy-cat murder based on one of his novels. He uses his connection with the Mayor to charm his way into shadowing the captivating Detective Kate Beckett. Castle decides to use Beckett as the model for the main character of his next book series starring "Nikki Heat". Beckett initially disapproves of having Castle shadow her on her cases, but later warms up and recognizes Castle as a useful resource in her team's investigations.
Sundays at 9pm
They're partners, whether she likes it or not.