When Marshall picks up smoking again, it prompts Lily, Ted and Barney, ex-smokers all, to succumb as well. Meanwhile, Robin gets a new co-anchor at her show.

Billie tries to cover up the fact that Zack is living with her from her parents, while also worrying that she'll ruin Christmas, just like she has in the previous years. Meanwhile, Nick (Abby's husband) attempts to impress their father.

The conviction of a woman found guilty of poisoning a banker is overturned when a laboratory essential to proving the case comes under scrutiny. The subsequent re-trial forces Brenda to ask Provenza's former partner for help tying up loose ends. Unfortunately for the team, more scrutiny occurs when they all discover Provenza's former partner is no longer the man he used to be.

Jake is taught the art of infidelity by Charlie, whose girlfriend is away for Christmas.

During a political protest an unhappy farmer threatens the U.S. Treasury building by parking his tractor full of explosives. Meanwhile, Loker has to bear down with a group of third graders in a field trip stuck in the Lightman Group offices.

Leonard fears the worst for his relationship with Penny when his mother visits, while Sheldon is nothing but thrilled with Beverly's presence.

Eric Delko becomes the expert winess for the defense, but this actually pits him against his old team.

Jay's guest is director James Cameron.

Joe, who has been living in a hotel room since separating from his wife, begins to think about renting an apartment. Owen's father humiliates him by taking away the demo car he had been using and instead gives the worst car on the lot, much to his wife's dismay. Terry sets out to find the rude driver who almost ran him down.

The Old Man offers a steak dinner and a cash prize as an incentive to boost profits; supercharged motorcycle; 1915 calculator; 200-year-old buttons that might have connections to George Washington.

Corey buys a huge 12-passenger hot air balloon; classic 1960 Gibson Les Paul guitar; Prohibition period medicinal whiskey.

Guest: Actress Sigourney Weaver talks about her role in the new movie "Avatar".

Tonight Stephen welcomes rapper & actor Snoop Dogg.

Hugh Grant, Zoe Saldana, Alicia Keys

The Tonight Show with Conan O'Brien welcomes actor Tom Arnold and a musical performance by Adam Lambert.

In a flashback several centuries ago, it is revealed that Kouga was part of the Kuchiki Clan as Ginrei Kuchiki's son-in-law, and was overconfident in the abilities of his zanpakuto. He helped put down a rebellion of Soul Reapers, but some grew suspicious of his power, and had him attacked. He cut down his attackers, but was framed for killing his own allies by a group of jealous high-ranking Soul Reapers. He was imprisoned as a result, but escaped with Muramasa's help. In the present, Kouga awakens, repelling Ichigo and Rukia, then suddenly stabs Muramasa.

Mark offers Judith his support after her teenage son is admitted to the hospital with alcohol poisoning. Elliot accuses Penny of being too close to Scott. Maria attempts to impress Daisha.