Chemistry: the study of change. Apply heat and, boom, no going back. Meet Walter White, high school chemistry teacher. Sleepwalking through life when, boom, a terminal diagnosis changes everything. Liberates him. Empowers him to use his chemistry skills anew: to man a rolling drug lab and finance the future for his struggling family. It's an uncontrolled experiment with the American dream. And it finally wakes him up.

Episode Summary: Skyler considers packing up the kids and leaving. Walt and Jesse's ongoing plan may be foiled by a new team member.