14. "I Am The One Who Knocks"
As Seen In: Season 4 Episode 6: "Cornered" This scene became one of the most iconic moments of the show, and so perfectly encapsulated Walt's transformation from meek schoolteacher to dangerous drug kingpin. At this point in the series, he still had Gus to deal with but was beginning to fully express his Heisenberg side even when in front of Skyler. Skyler is pleading that he go to the police, and it isn't until she starts to tell him that he's in over his head does he begin to slip. Cranston has gotten universal praise for this scene, but it would be tragic to overlook Anna Gunn, whose acting here brilliantly captures the fear that Skyler now has for her husband, and the utter disbelief in witnessing what he's becoming.