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.

Skyler gets involved with Walt's business. Hank struggles with his recovery. Jesse makes a startling discovery after meeting a girl at group therapy.

Walt attempts to form a new alliance as he plans his next move. Skyler pushes Walt towards a business opportunity, in hopes of protecting the family.

Events spiral out of control at Jesse’s place. Skyler reluctantly asks for Saul’s help. Marie returns to an old pastime and a friend asks Hank for help.

Skyler makes an unsettling discovery. Walter, Jr. pushes his dad into a questionable purchase. Jesse offers Mike some unexpected help.