Castle is an American television drama that aired on ABC from March 9, 2009 to May 16, 2016.
The series was officially cancelled on May 12, 2016, after eight seasons and 173 episodes.
"Castle" follows Nathan Fillion as Richard Castle, a famous mystery novelist who has killed off the main character in his book series and 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 is intrigued by this new window into crime and murder, and uses his connection with the Mayor to charm his way into shadowing Detective Kate Beckett, played by Stana Katic. Castle decides to use Beckett as the model for Nikki Heat, the main character of his next book series. Beckett, an avid reader of Castle's books, 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.
Nathan Fillion as Richard Castle/Richard Rodgers
Stana Katic as Katherine "Kate" Beckett
Jon Huertas as Detective Javier "Javi" Esposito
Seamus Dever as Detective Kevin Ryan
Tamala Jones as Dr. Lanie Parish
Ruben Santiago-Hudson as Captain Roy Montgomery (seasons 1-3)
Molly Quinn as Alexis Castle
Susan Sullivan as Martha Rodgers
Penny Johnson Jerald as Captain Victoria Gates (seasons 4-7)
Toks Olagundoye as Hayley Shipton (season 8)
Created by Andrew W. Marlowe, it primarily traces the lives of Richard Castle (Nathan Fillion), a best-selling mystery novelist, and Kate Beckett (Stana Katic), an NYPD homicide detective, as they solve various unusual crimes in New York City.
Detective Beckett is initially infuriated at the thought of working with a writer and goes to great lengths to keep him out of her way. However, the two soon start developing feelings for each other. The overarching plot of the series focuses on the romance between the two lead characters, as well as the murder of Beckett's mother.