Detective novelist Richard Castle (Nathan Fillion) is working on his own creation while still working as a "part-time job" for the New York Police Department. Although he has reconciled with his ex-wife Gina (Monet Mazur), he can't let go of his half "partner" in the New York Police Department-Detective Kate Beckett (Stana Katic). At this time, a guy who made Richard alert appeared in Kate's life-her trainer when she was a trainee police officer (Victor Webster). But what made him even more headache was that the little adult daughter Alexis (Molly C. Quinn) began to fall in love, causing him to always be suspicious of his daughter's boyfriend. At the end of this season, Kate was shot at her funeral, so that Richard could no longer ignore his inner thoughts, and finally confessed his love to her. It seemed that everything would be different...