"Smile Bones" is the twenty-ninth episode of Season 2 of Teen Titans Go! and the eighty-first episode overall. It first aired on 5 February 2015 on Cartoon Network.
When Cyborg and Beast Boy teach the other Titans to wolf down their food, the gang develops a big fat problem.
The Titans prepare for a proper dinner, Robin with pizza, Raven with salad, and Starfire with corn on the cob. Cyborg devours a whole sandwich without even biting. Robin claims that Cyborg didn't use his teeth, in which the robot is confused with. Beast Boy refers the teeth as "smile bones", as Cyborg replies who calls smile bones 'teeth'. Beast Boy recalls "people who don't know how to eat right". Raven quotes him they were inhaling their food, to the fact that Beast Boy inhales her, Robin, and Starfire's food. The latter tries to inhale a bit, but she chokes and spits the bit onto Raven. With Starfire congratulated by Beast Boy, he tells her that the point of eating is getting much food in your belly quickly.
Robin suggests that taking every bite is a point of eating. That ends up with Cyborg and Beast Boy's bellies, implying that they are nothing compared to their bellies. Starfire greets the bellies, and show that she has nine of them—none of them speak at all. Robin quotes that they were squeezing their fat around to the fact that they were talking, provided by Beast Boy and Cyborg themselves. Beast Boy's belly talks to him back that he was the fat one, and the Boy Wonder adds that BB and Cy speak for their bellies now, but later, the bellies will speak for them.
The next day, Beast Boy and Cyborg savor the food that the other Titans were about to eat; Raven's cereal, Robin's popcorn, and Starfire's picnic. Later, they were all hungry, so Cyborg throws a pizza at them. They all start to eat it, but Beast Boy and Cyborg devour the entire pizza, even a pepperoni topping. Cyborg quotes that they were complimenting the food before they can even eat it and Beast Boy says that they're eating "too slow". Raven gives up and asks the boys with her belly on how to eat the right way, and Starfire also gave up. Robin, suggesting that they give up just because of hunger, but then he immediately gives up.
Outside in the backyard, Raven, Starfire, and Robin lined up with their bellies, The former two spoke with their bellies, the latter one still claiming that her stomachs can't speak. All three give up their smile bones, as an eating montage begins. Raven swallows cookies, Starfire devours meat, and Robin gobbles up ham. They continue to swallow every type of food, as they are later given gold medals and their gold medals are received, but they obtained the wrong ones and then given their own teeth. The bellies speak yet again, and Starfire's nine bellies finally began to speak. They all argued that who would be the biggest belly. So they agree to belly up.
Another montage later, the Titans complained that their bellies are full. Beast Boy and Cyborg spoke with their bellies, but it wasn't them who spoke—it was actually their bellies, who become alive and gain eyes and mouths. They exit through the window, and Robin, Starfire and Raven need to catch up to them; before doing so, they have to take care of their bellies.
After yet another montage featuring the bellies wreaking havoc around town by devouring food, the two turn into gigantic bellies who continue to devour more food. Soon, the Titans arrive on the scene, helping the two how to eat properly. They give them fancy food, but not long before the bellies remove their teeth.
However, Robin and Starfire give the boys their "smile bones". Beast Boy and Cyborg in a fancy matter, while their bellies grew back to normal. The two learned their lesson about how to savor their food rather than gulping it down in one bite. That, and Robin agrees that his belly is in charge, claiming that it is big enough to devour the food, as the episode ends.
For a full transcript of "Smile Bones", click here.