Castle (2009)
S4E4 Kick the Ballistics
Episode Overview
As Castle and Beckett delve into the puzzling murder of a young woman, they confront a cop’s worst fear: the firearm linked to the crime turns out to be Det. Ryan’s former service weapon, which was taken by the notorious serial killer, 3XK. Racing against time, the team must unravel the mystery behind the murder, locate 3XK, and recover Ryan’s gun before the killer can claim another victim.