A death row inmate asks for Booth's help to prove his innocence before he is scheduled to be executed. Booth agrees and asks Brennan and her team to help him out.

Brennan is about to go out for dinner with her old professor and ex-lover when Booth asks her and her team to help identify the remains of a young woman found in a refrigerator.

Brennan and her team are brought in to identify the body of a man found in a fallout shelter. While cutting into the bones of the man, Zach accidentally releases a deadly fungus, causing the team to be quarantined over Christmas.

Brennan receives some bones to identify, but is stunned when she discovers that the remains are those of her mother who disappeared when she was 15 years old. The determined date of her mother's death leaves Bones confused and angry.

A cabin burns down in the woods revealing two bodies, one of a modern-day witch and one from the days of the Salem Witch Trials leading Booth and Brennan into the world of Wicca to find a killer. Meanwhile, when Hodgins' reckless driving gets him and Angela arrested and thrown in jail, Sweets and intern Clark Edison step into unfamiliar territory to help out the team

The investigation of the murder of a video-game designer reveals the wealth he accumulated during his career, which makes a suspect out of everyone who was in his inner circle. Meanwhile, "squintern" Jessica sheds light on an educational opportunity; and Brennan and Booth discuss Christine's future.

When the remains of famous billionaire explorer Henry Charles are found in Antarctica, the high profile case is brought to Brennan and Booth to determine if his death was a murder. The Jeffersonian team confirms he was killed when he went missing ten years ago on an expedition, but the timeframe puts the Jeffersonian's Dr. Clark Edison, who was with Charles for the expedition, on the short list of suspects. Meanwhile, Cam's sister comes into town to help with wedding plans and old family friction comes into the picture.