Ruggedly handsome crime novelist Richard Castle (Nathan Fillion) has been partnering with NYPD homicide detective Kate Beckett (Stana Katic) to solve murders for several years now, along with her loyal team of detectives Kevin Ryan (Seamus Dever) and Javier Esposito (Jon Huertas). The relationship between Beckett and Castle has grown closer over the years. In fact, it has reached a tipping point, as the two must decide what comes next for them. Meanwhile, there are still plenty of mysteries to solve – including the identity of the shadowy figures behind the murder of Beckett’s mother.