In the 100th episode we go back to see how Lisbon and the team first met Jane.
The NCIS team has a surprise in store for them when investigating the murder of a Navy lieutenant leads them to McGee's grandmother.
The General works to regain Scylla.
T-Bag gets a new partner.
Michael and Lincoln have an important meeting.
Nick is surprised when his father refuses to do the Christmas festivities in the house, and he decides to find a way to learn why. Physical Phil continues his tradition of pretending to be an architect when his parents come for a visit, which irritates his girlfriend. Eddie freaks out when Janet gives him a very personal Christmas gift. Owen and Alison end up in bed, but their happiness as a couple is soon put to a test.moreless
When an alien attaches itself to B'Elanna's nervous system, the Doctor enlists the help of a holographic recreation of an expert. However, when B'Elanna learns that the expert is a Cardassian that performed immoral medical experiments during the occupation, she refuses treatment.
Bachelor and bachelorette parties for Billy and Ellyn provide the backdrop for a look at the various couples' relationships with each other and their fidelity.