During breakfast at the Lucky Cat Café, Aunt Cass has trouble with the coffee machine. She tries to get it to work by whacking it several times with a rolling pin, but ends up breaking it, and causing a stray piece of the machine to ruin Fred's eggs. Fred himself, however, is missing, but Go Go soon receives a call from him, saying he needs urgent help. Thinking that Fred is in serious trouble, Big Hero "5" suit up and fly to Fred's Mansion, only to discover that he is fine and being groomed. Fred explains that his Bro-Tillion is coming up, which, according to Heathcliff, is a grand gala held in his honor where he will be presented to the city's money elite. Fred is not looking forward to it, especially since "Binky" is going to be there. Fred's mother comes in to check on Fred, while clarifying that Binky, better known as Beverly Samantha Mole, is the reigning queen of San Fransokyo's money elite, though Fred's mother considers her to be rude, arrogant, and quite insufferable; completely unlike herself. As far as Fred can remember, his eccentric behavior has been the subject of many of his mother's humiliations in front of Binky, including ruining a priceless artwork, letting monkeys out of their cages, and crashing a yacht into a building. Fred does not want to disappoint his mother, and pleads with his friends to help him become a proper gentleman.
His friends agree to help him out, starting with Hiro getting Baymax to teach Fred how to dance the waltz, using a dancing chip Hiro inserted into Baymax. While teaching Fred the waltz, Fred's mother comes in with news of an avalanche at the family mountain in Switzerstan, and Fred's father leading the rescue team, thus being unable to attend the Bro-Tillion. Heathcliff also announces that the caterer had just cancelled, and there are no replacements available. Mrs. Frederickson refuses to cancel the Bro-Tillion, despite these setbacks, much to Fred's dismay, though becomes distraught over the catering predicament. Hiro recommends his aunt to be the new caterer, hyping up her food as "cutting edge."
On the day of the Bro-Tillion, Aunt Cass is in the kitchen making the hors d'oeuvres, with Hiro, Baymax, Honey, Go Go and Wasabi serving as waiters and waitresses. While Mrs. Frederickson is introducing Fred to the money elite, the party is suddenly interrupted by a steaming super-villain known as Baron Von Steamer, who attempts to kidnap Fred and use him as bait to draw out Fred's father. The guests flee in terror, while Big Hero 6 tries to fight off Baron Von Steamer and protect Fred without the use of their gear. However, he mistakes Wasabi for Fred, and escapes with him instead. Puzzled by the connection between Baron Von Steamer and Fred's father, Fred shows his friends the secret den he found. Within the den, they find several items belonging to Fred's father, who was once known as the superhero Boss Awesome, with Baron Von Steamer being his arch-nemesis. They receive a surprise video call from Fred's father, who tells them the areas where Baron Von Steamer was frequently found. Fred rules out locations that he knows to be occupied by fast food stands, leaving two possible places where Baron Von Steamer could have taken Wasabi: the abandoned subway station and the old ironworks, both of which are on opposite sides of the city.
They split up into two groups: Hiro and Baymax check out the abandoned subway station, and Honey Lemon, Go Go and Fred check out the old iron works. Hiro and Baymax encounter a multitude of booby traps in the abandoned subway station, but ultimately find that Baron Von Steamer is not there. Meanwhile, Baron Von Steamer has Wasabi locked in a cage, and eagerly awaits for Boss Awesome to come to his rescue. Baron Von Steamer still thinks that Wasabi is Fred, despite being told the contrary multiple times. When Boss Awesome does not arrive at the strike of midnight, Baron Von Steamer starts to lower Wasabi into molten lava. Go Go, Honey and Fred arrive just in time to save him, with Hiro and Baymax joining them soon afterard. Baron Von Steamer brings in a giant steam-powered spider, armed with hammers and flamethrowers. At the sight of this, Fred's debilitating fear of spiders causes him to freeze up, while everyone else engages the old super-villain in a fight. All four members soon become incapacitated, and Fred is the only one still standing. Seeing that his friends are in trouble, Fred pushes himself to get over his fears and confront Baron Von Steamer, who finally realises that he is Boss Awesome's real son. Fred uses the dance moves he was taught to elude Baron Von Steamer's attacks, and uses his flamethrower to melt the spider's legs. Though defeated, Baron Von Steamer vows revenge upon Fred and escapes. Later, the remains of Fred's Bro-Tillion has been moved to the Lucky Cat Café, and everyone, except Binky, is having a good time. Aunt Cass has received more jobs for catering, and Mrs. Frederickson no longer cares about impressing Binky. Mrs. Frederickson tells Fred she is proud of him, and Fred embraces her, while looking at and following the steps Baymax has displayed on his screen.
|Hiro Hamada||Ryan Potter|
|Go Go Tomago||Jamie Chung|
|Honey Lemon||Genesis Rodriguez|
|Aunt Cass||Maya Rudolph|
|Fred's Dad||Stan Lee|
|Fred's Mom||Susan Sullivan|
|Baron Von Steamer||Debut||Jeff Bennett|
|Beverly Samantha Mole||Debut|
- This was the first episode of Big Hero 6: The Series to be produced.
- This episode was released on March 15, 2018, in the United Kingdom before its official US release.
- Beginning with this episode, all subsequent new episodes started premiering on Disney Channel instead of Disney XD.
- This and "Steamer's Revenge" are the only Season 1 episodes where the San Fransokyo Institute of Technology is not featured. Coincidentally, both are also the only episodes where Baron Von Steamer is the main villain.
- Fred is revealed to be arachnophobic.
- "Bro-Tillion" is a portmanteau of the words "bro" and "cotillion".
- A cotillion is a formal ball that presents debutantes as new adults, officially coming into society.
- Running Gag: Honey Lemon is terrified when someone eats an animal shaped cookie.