Wildly famous mystery novelist Richard Castle (Nathan Fillion) is bored with his own success. Then he learns that a real-world copycat killer has started staging murder scenes depicted in his novels. Castle is questioned by NYPD Detective Kate Beckett (Stana Katic), a bright and aggressive detective who keeps her investigations under tight rein. Though they instantly clash, sparks of another sort also begin to fly, leading both to danger and a hint of romance as Castle steps in to help find the killer. And once that case is solved, he and Beckett build on their new relationship as they look to solve more strange homicides in New York - as much fun as one can have with death and murder.