After a brief hiatus, "Bones" will return this Thursday with an exciting two-part midseason finale where Brennan (Emily Deschanel) and Booth (David Boreanaz) will go undercover in the wild, wild west in order to find a killer cowboy.

The first episode in the two-part finale, which is entitled "The Cowboy in the Contest," will mark "the return of Buck and Wanda," teased Deschanel in a new promo video, adding, "but this time it's 'Big River Buck' and 'Wildcard Wanda.'"

In a sneak peek video, Brennan surprises her husband by joining him at a bar where they introduce themselves to other saloon-goers as quick draw Wildcard Wanda and notorious highwayman Big River Buck. A red flag is raised when they also overhear the patrons speaking about an upcoming shooting competition and the reigning champion Slow Burn Stanley, who appears to have gone missing.

According to AceShowBiz.com, the synopsis for "The Cowboy in the Contest" reads as follows:

"To solve a murder, Brennan and Booth go undercover at an Old West-style shooting competition, while Angela and Hodgins discuss the future of their family and Cam gets close with photographer Sebastian Kohl (guest star Gil Darnell)."

The midseason finale will then conclude with another episode, which is titled "The Doom in the Boom" and will feature the Jeffersonian team will go on the hunt to find a cop killer.

"The first hour is a lot of fun, and then the next episode is very dramatic, some serious stuff goes down," says Deschanel in teaser video. "It's intense."

"The team investigates the murder of a police officer that sends shockwaves through both the Jeffersonian and FBI teams. Behavioral analyst Leslie Green (guest star Sara Rue) is assigned to work with Booth on the investigation and lends her professional assessments on who the cop killer could be, while Cam must make some decisions in her personal life and the entire team re-evaluates what is truly important to them," reads the synopsis, according to AceShowBiz.com.

The Season 11 fall finale, "The Cowboy in the Contest" and "The Doom in the Boom," will air on Thursday, Dec. 10, starting at 8 p.m. ET on Fox.

Watch preview videos below.