So, the title of the next episode was recently revealed to be "Not What He Seems," so, naturally, the theorizing will begin!
Not much has been revealed about it so far, but, it's never too early to start speculating!
The first question that comes to my mind is: who is "he?"
My answer: Stan.
Remember the cryptogram from the theme song? "Stan is not what he seems." This is going to be a big episode, possibly the one that reveals what it is Stan is doing with the universe portal. Maybe the twins finally learn what their uncle's been up to.