On “Brooklyn Nine-Nine” season 4 episode 18, Amy (Melissa Fumero) is stressed out because of the Sergeant exam. Meanwhile, Gina (Chelsea Peretti) destroys the Boyle family’s holy grail on “Chasing Amy.”

Spoiler alert: This recap contains plot details about season 4 of “Brooklyn Nine-Nine.” The fourth season premiered Sept. 20. The series is available for Australian viewers to watch on SBS every Wednesday at 8:00 p.m.

Amy is having difficulties before her Sergeant exam. She wants to become the youngest captain in the history of the NYPD, but the pressure is catching up with her. She is easily agitated and bursts with fits of rage.

Jake (Andy Samberg) sets up a simulated practice test for Amy in order to reduce her anxiety, but she walks out and disappears after a while. They try to call her from Terry’s (Terry Crews) phone hoping she’d answer her superior officer, only to discover that she left all of her things on her desk.

After a long search, Jake finally finds Amy. She says she did great on the practice test, but she’s afraid that passing the Sergeant exam might change things between him and her. Jake assures her that it’s going to be okay, and that she’s too good to be afraid of being successful. Later, Amy aces the test, finishing it 45 minutes early.

Meanwhile, Charles (Joe Lo Truglio) is jealous of Gina because their recently passed aunt left her the family’s “sour dough starter,” although she’s grossed out by it. Charles offers to take it, but Gina insists that he buys it from her for a very steep amount. By the time Charles has the money, Gina accidentally burns the whole mother dough.

Both Charles and Gina get banished by the Boyle family for the incident. Gina makes another mother dough to replace the old one and appeals to the family to let Charles back in, which they did.

Terry and Holt (Andre Braugher) have different opinions regarding the soft room’s model train station. Terry thinks that it should be done with a creative imagination while Holt wants it to be as real world accurate as possible. They split the train set into two parts to see which setup a witness’ child likes better, but the kid says trains are lame and that he only wants to play video games. The sergeant and the captain patch things up and play with their setup.

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