Secret Secret-Keeper: Adrien recognizes the Turtle and Horse Miraculous and figures out that Alya, Nino and Max are Rena Rouge, Carapace and Pegasus.
Ship Sinking: While Adrien thinks that Luka and Marinette are together, it's here that Luka decides to end what they have before they go any further because he isn't interested in being a step-dad. Since Marinette wasn't in-love with Luka, she isn't too broken up about it and they both agree to just be friends.