A mysterious little girl is abandoned at Briarcliff. The Monsignor makes a Faustian pact with Dr. Arden. The origin of Bloody Face is revealed.

Everyone in the firehouse is ordered to take a drug test after a call to a daycare center exposes them to a makeshift meth lab, and Severide stalls, not wanting his injury, or the painkillers he takes, to be discovered. Meanwhile, Truck and Squad find themselves pinned down by gunfire while trying to help the victim of a gang shooting, and a deep-fried turkey fire grows from small to explosive when a garage catches fire. Elsewhere, Dawson saves a bleeding man and Casey delivers a baby on the scene of a massive car pileup on the freeway.

The BAU team goes in pursuit of a missing school bus full of children outside the Washington, D.C. area, and it becomes a race against time for them to bring them home safely.

When eight bodies are found in what appears to be a meteor site in the middle of the desert, CSI Finlay recognizes one of the casualties, prompting her to revisit her past.

Sketches include gangsters sharing a passion for the movie "Twilight"; a visit to a world where names are farts; racist superheroes.

From "Hitchcock," actress Scarlett Johansson; musician Willie Nelson; musical guest Gary Clark Jr.

As the detectives investigate reports of sexual abuse at an elite private school, decades of secrets are exposed.

The foodies serve up assorted dumplings featuring various global tastes. Then, it's a battle between Emeril Lagasse and Tom Colicchio when the two celebrity chefs lead teams in a grand-scale Thanksgiving-theme challenge. Guest judge: Dana Cowin.