"Our Idiot Brian" is the eighth episode of the thirteenth season of the animated sitcom Family Guy, and the 239th episode overall. It aired on Fox in the United States on January 11, 2015, and is written by Aaron Lee and directed by John Holmquist. The title is a play on the film Our Idiot Brother. The episode centers on Brian failing an SAT test, leading the family into thinking that he is not as smart as he claims to be, although Peter shows him the upside to being unintelligent. The cause of Brian's change in behavior is found to be a brain tumor, and Stewie longs for Brian to have it removed to return to normal.

Meg worries about passing her SAT to get into college, so her friends suggest she hire a smart person to take the test for her. She convinces Brian to do so, flattering him by reciting quotes from his novel Faster Than the Speed of Love. Brian disguises himself as Meg, goes to school and takes the test for her. Meg shows Brian that he failed badly, scoring just 1,000 out of 2,400. Chris decides to spread the news and rides off on his horse Artemis. When he arrives in the village, Chris forgets what he is going to say and assumes that the news is that Brian is getting another book published. After Chris leaves, the villagers are relieved that the news is not about another Meg episode.

Peter tries to get Brian to look on the bright side of being less intelligent, and together they do low-brow activities like watching a demolition derby and visiting Orlando, Florida. However, Stewie is puzzled about Brian's change in attitude as being very uncharacteristic of him.

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