On tonight’s episode of The Big Bang Theory, the gang is excited for Christmas.
Well, everyone except Sheldon.
Will he realize the true meaning of the holiday and get into the spirit before the end of “The Clean Room Infiltration?”
Here are some highlights and pictures from the episode.
1. Sheldon Is Mad at Amy

(CBS)
He is not happy that his girlfriend kissed him under the mistletoe. Since they mutually decided not to buy one another gifts, Sheldon decides that getting her one would ruin her holiday.
Bernadette takes Sheldon to the mall, and he admits that he loves Amy, but also wants to make her miserable.
Of course, Amy has a surprise gift for Sheldon as well.
2. Amy Throws a Christmas Party

(CBS)
Amy goes all out and plans a Victorian Christmas for her friends. She plans parlor games, and makes goose and figgy pudding.
Raj and his father, Dr. Koothrappali arrive and then Raj gets a call and has to leave to help Leonard and Howard at the lab.
Amy and Penny regale him with stories of Raj.
3. There’s a Lab Accident

(CBS)
Leonard and Howard are in a clean room doing an experiment. They are building a multi-wire detector to track cosmic particles.
“If we were still single, we’d be tripping over all that booty,” Howard says.
As they go to leave, a pigeon flies into the room, and the boys freak out over their ruined work. Watch the sneak peek below.
4. Raj’s Parents Are Divorcing
In the clip above, we see Penny ask Raj about his parents. “Not great, they hired divorce attorneys,” Raj replied, sounding defeated.