Matt McTighe

The race for the Chief's position is on, as the doctors compete for Richard's affections, a surgical patient endangers the lives of those around her, and Meredith's Alzheimer's-stricken mother, Ellis, experiences a change in her medical condition.

The CBI team investigates when the body of a female army medic who worked with soldiers suffering from PTSD is found near a military base.

When a man dressed as Santa Claus blows himself up during a botched bank robbery, Brennan and Booth work to identify the bomber and determine his motives. Meanwhile, Brennan makes plans to spend Christmas in El Salvador, but her father (guest star Ryan O’Neal) convinces her to spend the holidays with him and Margaret Whitesell (guest star Zooey Deschanel), a newly discovered distant relative.

A professional hit man (Max Martini) with information about the murder of Beckett's mother escapes during a court hearing; Castle and the team uncover a deep conspiracy.

The team must stop a gang of suspected murderers that is targeting a new victim nightly.

Maura meets a man in an unusual way; Jane has mixed emotions when someone from her past returns.