1. Seven Thirty-seven -

Fearing for their lives, Walt proposes a plan to kill Tuco using ricin, a potent toxin.

The title has a dual significance that layers immediate plot goals with long-term foreshadowing: 1. Seven Thirty-Seven

When combined with the titles of other episodes featuring black-and-white flash-forwards ("Seven Thirty-Seven," "Down," "Over," and "ABQ"), the phrase "Seven Thirty-Seven Down Over ABQ" is formed, foreshadowing the mid-air collision of a Boeing 737 at the end of the season. Plot Highlights Fearing for their lives, Walt proposes a plan