When an unassuming high school chemistry teacher discovers he has a rare form of lung cancer, he decides to team up with a former student and create a top of the line crystal meth in a used RV, to provide for his family once he is gone.

Walt and Jesse attempt to tie up loose ends. The desperate situation gets more complicated with the flip of a coin. Walt's wife, Skyler, becomes suspicious of Walt's strange behavior.

Walter fights with Jesse over his drug use, causing him to leave Walter alone with their captive, Krazy-8. Meanwhile, Hank has a scared straight moment with Walter Jr. after his aunt discovers he has been smoking pot. Also, Skylar is upset when Walter stays away from home.

Walter finally tells his family that he has been stricken with cancer. Meanwhile, the DEA believes Albuquerque has a new, big time player to worry about. Meanwhile, a worthy recipient is the target of a depressed Walter's anger, and Jesse makes a surprise visit to his parents home.

Walt's secret is in jeopardy when Skyler thanks Gretchen for paying for his treatment.

Skyler confronts Walt about his secrecy; Jesse falls apart; and Jane's grief-stricken father takes action that results in further tragedy.

Walt faces a new threat, on a new front and deals with an increasingly angry Skyler, who must consider what to do next with her life and the kids. Meanwhile, Jesse comes face-to-face with some startling self-revelations.

With Jesse on the run and Mike in hot pursuit, Walt negotiates a bargain with Gus and concocts a disturbing plan to provide for his and Jesse's safety.

Walt and Jesse face the deadly consequences of their actions. Skyler deals with a puzzling disappearance, as Marie struggles to help Hank with his recovery.

Walt and Jesse team up to take on Gus. With Saul's help, Walt finds an unexpected ally.

As Walt deals with the aftermath of the Casa Tranquila explosion, Hank works to wrap up his investigation of Gus' empire.

Walt and Jesse pursue an unlikely business partner. The DEA filters through various leads in hopes of finding something.

All bad things must come to an end.