Sally walks in on Roger getting a blow job from Megan's mother – Episode Seven, 'At the Codfish Ball'
The theme for Sally this season is without a doubt "I'm Not a Girl, Not Yet a Woman" – culminating in the arrival of her first period in the penultimate episode. Wherever she turns, she's met with another facet of the seedy underbelly of adulthood, whether it's student-nurse murders or learning her father had another wife before Betty or Megan. But nothing could have prepared her for the sight of her step-grandmother with a mouth full of Roger Sterling. Kiernan Shipka superbly conveyed Sally's revulsion, not just in her facial expression, but when she summed up New York in one word to Glen Bishop: "dirty."