Bones

Booth: Kyle hit the Duke with the candlestick in the crypt. (Booth & Goodman laugh) Brennan: What? What's the joke? Booth: Clue. Brennan: What Clue? Booth is referring to a popular board game (called "Clue" in the US and "Cluedo" in the UK) where the players have to work out who killed Mr. Boddy (or Mr. Black depending on the version) with what weapon and in what room of his mansion, using a limited set of who, what and, where cards.

Booth: You know Treasure of the Sierra Madre but you don't know Charlize Theron. The Treasure of the Sierra Madre is the name of a 1948 movie starring Humphrey Bogart.

The documentary about underground tunnels and the society found within bears a strong resemblance to Dark Days, a documentary by Marc Singer.

LeMat A Civil War repeating pistol designed by Jean Alexander Francois LeMat, a French gun designer who was also the son-in-law of a Confederate major. To increase the revolver's military utility, LeMat built a 9 shot, .44 caliber cylinder, giving it three extra shots and more punch than the .36 caliber Colt. The LeMat revolver is most often remembered, however, for the 10th shot. LeMat put a second barrel under the normal .44 caliber barrel, around which the cylinder revolved. This second barrel was a single shot, .65 caliber 18 gauge shotgun - short, with very little range, but a nasty weapon up close, effectively a sawed off shotgun hidden in the middle of the pistol.

Rangers The 75th Ranger Regiment, also known as the United States Army Rangers, is a Special Operations Force of the United States Army Special Operations Command (USASOC), with headquarters in Fort Benning, Georgia. The Regiment is a flexible, highly trained and rapidly deployable light infantry force with specialized skills that enable it to be employed against a variety of conventional and special operations targets. Their motto is "Rangers lead the way!"

Tenth Special Forces Group The 10th Special Forces Group was activated June 1952. It is assigned to the U.S. Army's Special Operations Command located at Fort Bragg, N.C. The group trains for and conducts combat, unconventional warfare, special reconnaissance, and foreign internal defense missions.