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..

Walter finally tells his family that he has cancer. Meanwhile, the DEA believes Albuquerque has a new, big time player to worry about. Jesse makes a surprise visit to his parents home.

Walter and Skyler attend a former colleague's birthday party. Jesse tries to free himself from drugs, while Skyler organizes an intervention.

Walter accepts his new identity as a drug dealer. Elsewhere, Jesse decides to put his aunt's house on the market and Marie throws Skyler a baby shower.

The side effects of chemo begin to plague Walt. Meanwhile, the DEA rounds up suspected dealers.