Stewie meets Penelope, a preschool-aged girl who may be just as evil as he is, while Lois gets separate beds after suffering a back injury from Peter sleeping on her, and Peter decides to cuddle with Quagmire after being unable to adjust to SleepingSingle.

!!Tropes

* AbandonedCatchphrase: Lampshaded:
-->'''Stewie:''' I've always been about world domination. What the hell do you think I was talking about when I said "Victory shall be mine!" \\
'''Brian:''' You have not said that in a very long time.
* AllJewsAreCheapskates: Stewie replaces Mort's wallet with a wallet bomb, set to explode when it is opened. Two weeks pass, and Mort is still unharmed. He only opens the wallet after another bomb (that is triggered by him burping into his hand) is planted, and he checks to make sure his wallet's okay, only to be blown up a second time.
-->'''Penelope:''' Bloody hell, how do you go ''two weeks'' without opening your wallet? \\
'''Stewie:''' He's been out to dinner, like, four times!
* DisproportionateRetribution:
** Penelope gives the kid that shoved Stewie a piece of candy laced with superglue, causing him to graphically choke to death (even ''[[ClawingAtOwnThroat clawing at his throat]]''). Stewie has no objections to Penelope doing this.
--->'''Stewie:''' ''[[BondOneLiner Don't push]].''
** Pakistan’s response to India (actually Penelope) saying “up yours” to them is a series of nuclear missile strikes.
--->'''Stewie:''' They do not need much.
* EvilerThanThou: Penelope is eventually revealed to be even more immoral than Stewie.
* ForTheEvulz: Brian tells Stewie that his actions were all for the goal of World Domination while Penelope has no justification for most of her crimes, she just "loves to create chaos for the sake of it".
* FriendVersusLover: After Brian tells Stewie that Penelope might be a bad influence, Penelope orders Stewie to kill Brian, and when Stewie can't bring himself to do that, Penelope decides to just kill him herself.
* InstantSedation: Stewie considers using chloroform to kill Brian, but ultimately can't go through with it. At that, Stewie sneezes and instinctively covers his mouth with the chemical-soaked cloth, which almost instantaneously knocks him out.
* {{Matricide}}: Unlike Stewie, Penelope actually went through with killing her own mother.
-->'''Stewie''': Did you kill your mother? \\
'''Penelope''': Well, I held the knife. (''Smirking'') And her hair.
* SpecialGuest: Creator/CateBlanchett as Penelope.
* UnholyMatrimony: Stewie and Penelope. Both of them are evil masterminds, and in this episode, the two of them fall in love and cause havoc together.