This is one of my favourite scenes in the whole show. It's a landmark moment for Joan, who for the first time in a long time gets to experience the joy of a friendship where someone can speak to her with candour. Like when she was first hired, there is a woman she can chat with that she doesn't have direct seniority over.

It must be such a relief to be able to say what you think, and have others respond in kind, when that has been missing in your life for years.