The Doorway (1)mad Men : Season 6 Episode 1 -

The title refers to more than just physical entrances. It represents:

The episode is bookended by the concept of passing through to "the other side," specifically through the story of the veteran Don meets at the bar. The Doorway (1)Mad Men : Season 6 Episode 1

This episode features the "New Betty," who has dyed her hair dark and is attempting to find herself through social work and empathy, a sharp turn from her previous seasons. The title refers to more than just physical entrances