As we found out last week, Jake and Amy are having a baby! They didn’t do a very good job of hiding the news from the rest of the Nine-Nine, rendering their big announcement very anticlimactic, but they still invite the squad to the gender reveal party they’re throwing. When Jake tells his dad the big news, his dad is less than helpful. He tells Jake he hopes it’s a girl. Apparently, Peralta boys don’t get along with their fathers. Jake didn’t get along with his dad and Jake learns that Jake’s dad didn’t get along with his dad and so on. This makes Jake panic. 

Because Jake reconciled with his dad, he decides his dad should reconcile with his own dad. Jake calls his grandfather, Admiral Walter Peralta, and invites both him and his dad to the gender reveal party. Jake’s father and grandfather arrive early and the two of them hash out their differences. The fight ends with a friendly beer toss (they both loved playing catch when Jake’s dad was a kid) and the destruction of the gender reveal cake as it falls off the counter and onto the floor. No one knows the sex of the baby. So the Peralta men make blindfolds and blindly try to clean up the kitchen. Yeah, that doesn’t work. Now the entire kitchen is blue. 

Jake still wants to keep the secret from Amy so he calls in reinforcements. By reinforcements, I mean Boyle. Boyle makes a new cake for the party in record time and the Peraltas scrub away the blue. The plan almost works. But there’s just one problem, when they go to cut the cake, the cake is green. Oh, and Jake’s dad’s thumb is in the mix. Gross. Jake takes his dad to the ER and his dad tells him that he’s going to be a great dad because he already cares so much. Amy still doesn’t know the gender of their child so Jake gets a small cake for just the two of them. But when they go to open the box, the cake is gone. Then Scully walks in the room with his face covered in blue cake and icing. Now Amy knows they are having a boy!

Back at the Nine-Nine, Amy and Rosa work an important case that the mayor is involved in. However, they didn’t realize how important that case was and they pawned it off on Hitchcock and Scully. They work on tracking down a witness and get furious when they find out that Hitchcock and Scully didn’t take down the witness’s contact information. It turns out they were protecting the witness. Maybe they aren’t such bad detectives after all. Even Amy and Rosa admit they made the right call. 

Meanwhile, Terry is working on an audition for the NYPD marching band. He plays the flute and his audition song is “Muffin Man”. Holt is appalled and tells Terry he’s not good enough so he helps him prepare for the audition. Holt is a very intense instructor. In the end, Terry is the only flautist who auditions and gets to be in the band.