Complete story — includes the ending
With Castle having less than 24 hours before he succumbs to the effects of a deadly toxin, Beckett and McCord race against time to track down both the toxin and the antidote to save him and prevent more people from being killed. Their search takes them deep into a mystery involving a highly classified military base, a secret mission, and a coverup that reaches the very top of the Department of Defense.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, Castle season 6. HTML formatting and reference markers removed. · Content license