Rick Castle (Nathan Fillion), handsome and fun-loving mystery writer, first connected with the NYPD to help solve a series of murders ripped from the pages of his famous novels. Suffering from writer’s block, Castle found a muse in beautiful and smart NYPD Detective Kate Beckett (Stana Katic). Pulling strings to weasel his way into shadowing her, their partnership inspired Castle to write a new series of books. Teaming Castle’s writer’s intuition and Beckett’s creative detective work, they’ve spent eight years solving homicides in New York…and reluctantly falling in love.
Banter flies faster than bullets as Castle's approach to crime solving eventually wins over Beckett. Yet their flirtatious and fiery personal relationship is on rocky ground as it works its way into solving the strangest homicides New York has to offer. Castle's wildly funny storytelling skills seep into every case, and between his mixed-up partnership with Beckett and relationships with his diva mother and clever daughter, he’s always on his toes.
Everything changes when Beckett is shot. Castle works to identify the shooter as Beckett struggles with the aftermath of her near-death encounter. All the while, they tackle a new batch of cases. When the Triple X Killer returns to New York, the entire team races against the clock after Castle and Beckett go missing.
Together at last! Now that Castle and Beckett ("Caskett") have finally given in to their feelings, how will it affect their work? As they try to keep their new relationship quiet, the duo must continue to solve cases. The action and passion heat up, especially with Castle's stunning proposal to Beckett.
As they juggle wedding plans and their most intriguing cases yet, Beckett's new job with the Justice Dept takes her away from the wisecracking love of her life. But Castle's devotion to his fiancée -- and her fascinating line of work -- jeopardizes her career and creates a chain of events that might separate them forever.
Wedding bells are ringing, but will Castle and Beckett really tie the knot? On the biggest day of his life, Castle is nowhere to be seen...and not because he has cold feet. Finally found two-months later, with no memory of the lost time, will the truth of Castle’s disappearance come back to haunt the newlyweds? After passing the Captain’s exam, Beckett was surprised with the news that she was also being vetted for political office. Which path will she choose, and how will New York’s famous couple adapt?