"The Greater God" — The death of a Wall Street puts the team on a collision course with Gates' sister.
A guilt-ridden woman confesses to a murder, but contradictory evidence and a second confession complicate the case.
Castle and Beckett replicate the '70s to solve a murder.
When Castle and Beckett learn that a murder victim may have been poisoned at an Old West-style resort, they visit the resort posing as newlyweds to uncover the truth.
Castle and Beckett's long-awaited wedding is almost here, but when a shocking surprise threatens to ruin the big day, they are sent on a wild mission filled with masked men, angry bikers and a charming ne'er-do-well from Beckett's past.
When Richie “The Pitbull” Falco, a larger-than-life personal-injury attorney is found dead, Beckett and Castle investigate the many clients and competitors who had motive to kill him.
A murder investigation launches Castle into what seems to be an alternate universe where he's never met Kate Beckett. Castle has to convince Beckett, Esposito and Ryan -- now complete strangers -- to let him participate in their investigation so he can find his way back to his own world.
A secret investigation conducted by Beckett related to her mother's murder goes awry when a man she has been surveilling is killed. When evidence links Beckett to the victim, she and Castle become the target of a manhunt that puts both of them in grave danger.
When an ER physician is gunned down in the street, Castle and Beckett soon discover that the victim was a mob doctor to a Mafia family run by an old friend of Castle's.
When the star of Castle's favorite '80's action movie is mysteriously murdered, Castle and Beckett delve into the victim's secret past and pursue his killer with help from a team of aging action heroes.