Danny the new cast member and to make Jenna really angry, Pete wants him to sing in TGS' Christmas show. Ultimately, though, Jenna was placated yet again and Pete is still going crazy. So it goes.
Jack and old high school friend Nancy (Julianne Moore) met on YouFace, which led to a new love interest for Jack. Even if she's married.
Kenneth tried to do Secret Santa with everyone again (which they hate). The guys try to make up their own religions to get out of it.
Liz was more of a supporting player in this episode, not having the main plot but getting involved in Jack and Nancy's relationship.
It was a Merry, funny Christmas all around!