Lisa befriends a highly creative girl (Emily Blunt) who develops, with Lisa, a fantasy world only the two of them share. As they go deeper and deeper into their make-believe universe, Marge becomes concerned. She forbids Lisa to see her new friend again, but Lisa defies Marge and runs away with Juliet. Lisa discovers that living a life of fantasy is increasingly unpleasant, and in the end is greatly relieved to return to reality. Featuring the music of Josh Groban and closing credit theme by Fallout Boy.