Castle and Beckett investigate who was behind a fatal bombing at a protest.
Tropes:
- Ambition Is Evil: Leann's motivation to help Jesse bomb his own demonstration was because she wanted a promotion from field reporter to anchor and figured she could get one by covering a major event like a bomb attack.
- Hoist by His Own Petard: Jesse was among the 5 fatalities of the explosion when he found his bomb (abandoned by a pickpocket moments earlier) right before it detonated.
- Internal Reveal: Castle finds out that Beckett did in fact remember the Dying Declaration of Love that he made to her after she was shot at Montgomery's funeral and that she lied to him about it.
- Unwitting Instigator of Doom: Bobby the pickpocket moves the bag containing the bomb from the dumpster (which would have contained the blast as the bombers intended) to out in the open, where it would kill 5 people upon detonating.
