← Previous Next → 4x16 Linchpin (Part 2) 4.68/5 (19 votes) First Aired: Feb. 20, 2012 on ABC Summary: 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.

Main Characters in this Episode

• Richard Ca…
• Martha Rod…
• Alexis Cas…
• Captain Vi…

Guest Stars Kate Beckett played by Stana Katic Javier Esposito played by Jon Huertas Kevin Ryan played by Seamus Dever Lanie Parish played by Tamala Jones Sophia Turner played by Jennifer Beals Martin Danberg played by Josh Stamberg Thomas Gage played by David Chisum Janacek Spivey played by Jim Turner Chess Player played by Cal Gibson Jones played by Russell Edge Tech #2 played by Burnadean Jones Tech #3 played by Lak Rana Agent Jack Corrigan played by Jade Carter Agent Trahn played by David Lim (IX) Super played by Steve Kramer (XV) More