Episode five changed the series for the better. Instead of just Ange being a badass all episode every episode long, it showed her cooperating with another warrior of equal or greater skill, Chise Todo, and them being badasses together. In fact, every member of the spy group did really well this episode, from the princess making good snap decisions, to Beatrice having the courage to face off against a pro assassin even though it didn't go very well, to Dorothy seeing a suspicious person and intercepting him before he could complete his nefarious plan. Everyone was competent and everyone worked together for the mission to succeed. It was just splendid.
And then when you have the amazing musical score of Yuki Kajiura in the background and the gorgeous animation that makes even standing up a work of art, you have the perfect storm.
Everything in this series just clicks. Even the fact that it concentrates on spy missions, something no other ranked anime has done before. It's carved out its own niche to shine in.
For now, Princess Principal can be my last ranked, 192nd best anime. Once the show is over I can judge it more properly.
My best guess is that Princess Principal is the only new great anime of the summer season. Action Heroine Cheer Fruits is too much of an oddball, Tenshi no 3p! is a retread, and Gamers! is hilarious but not very realistic. I don't see any of them crossing the threshold of quality that Princess Principal did with this ep.
I had no expectations for this show, and it turned out to be the best this summer.