"Lois Comes Out of Her Shell" is the sixth episode of the eleventh season and the 194th overall episode of the animated comedy series Family Guy. It originally aired on Fox in the United States on November 25, 2012, and is written by Danny Smith and directed by Joe Vaux. In the episode, Lois has a midlife crisis leaving Peter desperately trying to keep up with her. Meanwhile, Stewie adopts a turtle from the park, but the turtle is determined to kill Stewie.

Lois is not looking forward to her birthday, but Brian suggests throwing her a surprise party. After Peter reads a poem that lowers Lois' spirits even further, she decides to turn her life around by adopting a different, younger lifestyle with longer hair after a makeover and shopping trip.

Lois' lifestyle causes conflict within Peter, who is not sure about the changes but certainly likes most of Lois' new persona. But her new lifestyle soon begins to wear on him. When he gets tired at a party, he becomes a drag on Lois and she splits to party with younger girls. Back home, Peter moans about her behavior. On television, a report regarding Justin Bieber shows Lois hanging out with the teen girls. Lois sneaks into the concert intending to seduce Bieber but Peter bursts in and beats him up. After Peter demands that Lois come home and start acting her age she refuses, citing what he said to her. Peter apologizes and admits that he really likes Lois for who she is. When Bieber is called back onstage Peter is forced to go out and substitute "Conway Bieber". Back home, Peter reiterates his love for Lois, but mistakes her age. After she corrects him, he says "Get out of this house."

Meanwhile, Stewie Griffin finds a turtle in a pond in a park and decides to take him back home as his pet and names him Sheldon. Sheldon decides to avenge his removal from his natural environment by ruining the family's life. When Stewie has a close call with Sheldon in the vicinity he begins to get suspicious. Sheldon's attempt at revenge is revealed late one night and Stewie is forced to flush him down the toilet. When he reaches the end of the sewer pipe, he returns for more revenge. Stewie finds Rupert's and a stranger's head in boxes and vows to get even with Sheldon. After Sheldon bursts into Stewie's room for a showdown, Stewie nearly loses his fight until Mario jumps on Sheldon and kills him.

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