Peggy desperately tries to save Dr. Wilkes with a dangerous plan to stop Whitney Frost. But Thompson makes a surprising move that could destroy them all.

Peggy and Sousa propose a trade with Whitney Frost, while the SSR gets help from Howard Stark that may be the key to eliminating Zero Matter.

Castle & Beckett race to find the “Linchpin” in order to stop the first domino in a chain of events which will plunge the United States into war. Their efforts…

Castle and Beckett pursue a ruthless killer who, they discover, is part of a sinister, international conspiracy. Castle and Beckett are joined on the case by Sophia Conrad, a smart,…