Geez louise! You'd think this was Attica or something, as many escape attempts as we have. The girls were watching a movie in the dark in the living room with their rats (in their rolling balls). Jess had taken the top off Little Missy's ball and set it on the floor hole-down so Missy couldn't roll it, then put a book on top (of a round object???) to weight it down. Apparently neither geometry nor physics is really a strong point for Jess.
Anyway, Missy escaped and a frantic search ensued when the girls discovered her missing. Adrian was the one who actually found Missy -- she'd gone back to Jess' room and was trying to get to her cage. What a smart rat! No harm, no foul, but hopefully they learn a lesson from this.