|Jackson Hunt (alias)|
|Significant Other/s||Martha Rodgers|
|Children||Richard Castle (Son)|
|Other family||Alexis Castle (Granddaughter)|
|Portrayed by||James Brolin|
Jackson Hunt is the alias of a CIA agent and Richard Castle's father.
After meeting Martha Rodgers, he fell in love with her. He had planned on quitting the CIA after one last mission but was forced to go into hiding when it went south. It was a year before he returned to the US and found out about his son's birth. However, his profession refused any type of contact or connections to anyone, but Hunt continued looking after his family, even giving Castle a book in a library when he needed it (the book he gave Castle inspired him to become a writer) and reading all of Castle's books. Whilst his son was writing his Derrick Storm books, he arranged for Castle to be given access to the CIA so as to learn about its workings to help with his books, later hinted at by Sophia Turner. Hunt would work hard over the years to ensure Martha, Castle and Alexis were safe from his enemies.
He later found out about his granddaughter Alexis' kidnapping. This kidnapping was planned by an enemy of his, Gregory Volkov, who desires revenge against him for killing his wife during a CIA mission twelve years ago. He tracks down one of Alexis' kidnappers, Roger Henson, and tortured information out of him before killing him, later storming Henson's apartment. Eventually, he ran into Castle when he saved his son from getting killed by some of Volkov's goons. He confirmed he was a good guy and told Castle to grab the bag of money Castle brought with him, in an attempt to pay for Alexis's release, before heading to a safe place.
Once they were at his safe house, Castle questioned why he had pictures of Alexis and why he was helping. Suddenly, Castle's cloned phone, which Hunt set up so it couldn't be traced, began ringing and the latter assumed it was Beckett, but the former believed it was Alexis because it was a local number. They were wrong on both counts, as the caller was Volkov, demanding that Hunt surrender himself if he valued Alexis' life. Following this, Castle started pestering Hunt with questions, forcing him to reveal that he was Castle's father and the real reason Alexis was kidnapped. Together they planned on how they were going to free Alexis, and he told Castle his last words in case he wasn't going to make it. The plan involved Castle purposely getting captured. As Volkov demanded that Hunt surrender himself, it is revealed that Castle's radio contained an explosive, killing Volkov and creating confusion. Castle then freed Alexis with an explosive watch and made their way through their pre-planned escape route right into the American embassy, where they would receive a cover story for their return home, while Hunt assaulted the front of Volkov's base to keep his men occupied.
It is unknown if Hunt survived this operation, but after the mission Castle received a package that has a Casino Royale book (the book he gave Castle when he was a kid) inside implying that he survived.