The episode begins with Sonic enjoying a Sunday afternoon joyride in the canyon in his Sonic Speedster vehicle when Tails arrives in his own vehicle with a hoverboarding Knuckles behind him; Sonic challenges him to a race, and he accepts, all the while not paying attention to Knuckles colliding into several rocks and getting increasingly dazed. However, Sonic must abruptly call off the race when Amy contacts him on his Communicator for something important... asking for eggs so she can complete a recipe. Sonic activates his pedal-powered boost and speeds toward Hedgehog Village, leaving Tails and a completely stunned Knuckles (who says he "can live with" Sonic ending the race prematurely) in his dust. However, on his way in, he splashes a grocery-buying Eggman with mud, annoying the doctor; apologizing for the accidental mud bath, Sonic allows him a chance at retribution by splashing him with mud, but Eggman's attempt only gets him more soaked. Furious, Eggman summons his robots to attack Sonic, but as per usual, the hedgehog wins the battle, and Eggman only gets jeers from the villagers as a "reward". Considering himself the victim here, Eggman wonders what could have possibly brought this jeering about, and Sonic's quick to pin the blame on the supervillain's regular misdeeds; this gets Eggman thinking of a way to improve his image.
He's quickly inspired when he comes across a crowd of villagers buying a just-released Tommy Thunder video game, and it is massive— Mark the Tapir can hardly keep the crowd back, and then fails entirely when Tommy himself says stock is limited, getting trampled upon. And so Eggman gets to work on his own video game, which he titles 'Stache Smash. Upon the game's completion, he puts it on sale and attempts to get the villagers to buy it, but everyone passes him by, disinterested; Tails and Knuckles come nearby, and Eggman tells them about the newest, coolest game on store shelves, but of course, they (and an injured Mark, who somehow managed to make it to the job) mention different games entirely. Upon Eggman's explanation of what his game is and how it plays, Tails and Knuckles criticize the game for lack of features and outdated aspects, saying motion-capture technology is all the rage in games nowadays and that it improves a game's quality.
Further inspired by this advice, Eggman decides to make an enhanced version of the game with motion-capturing called Super 'Stache Smash; he later attacks Hedgehog Village with his robot hordes, Spy Bots in the wings to record Team Sonic in battle so he can recreate their abilities accurately in the video game. After a short while, Team Sonic inevitably dismantles the robots, and Eggman tells the Spy Bots to record him as he exits the Eggmobile and performs his own stunts... which are, as you would imagine for a man of his athleticism (or lack thereof), completely horrible. Team Sonic watches this, with Sticks wondering if they should retaliate against him or if his moves are embarrassing enough; Sonic puts aside the fact that he'd feel bad Spin Attacking Eggman over the horizon and, well, Spin Attacks him over the horizon.
After returning to his lair, Eggman watches the footage along with Orbot and Cubot, and needless to say, Eggman's dissatisfied with his clumsy stunts. Taking Orbot's subsequent suggestion (as his own, anyway) and deciding he needs someone with far better fighting skills than himself to serve as his motion capture stand-in, Eggman endeavors to find a foe of Sonic he knows that can really give him a challenge. He tracks the foe— none other than Shadow the Hedgehog— to the canyon and offers him a proposition; however, undoubtedly due to the fact that Eggman robbed him of the opportunity to finish off Sonic the last time they teamed up (to use the term loosely) due to an ill-timed "victory selfie", Shadow makes it clear that there's a 0% possibility of him ever working with the doctor again and bluntly tells him to get lost. Eggman, likely aware that Shadow would have no qualms against assaulting him if he persisted, has no other choice but to drop the attempt and walk away, all the while grumbling to himself in irritation.
With the direct approach to recruit Shadow having failed miserably, Eggman quickly formulates a plan B: resort to more underhanded means to get Shadow to fight Sonic. Therefore, he goes to Sonic's Shack and interviews Sonic about Shadow, hoping to goad him into insulting his rival. Instead, Sonic simply makes neutral remarks about Shadow and gradually gets more suspicious about Eggman's motives in asking him these questions, prompting Eggy to leave abruptly. Forced to work with what he's got, Eggman later goes to a cave Shadow apparently lives in (much to his annoyance) and shows him a video of the interview, which has been edited to make it sound like Sonic's trash-talking him; despite the poor quality of the editing, which makes it incredibly clear that it's been tampered with, Shadow somehow takes the bait and is far from happy that Sonic dared to insult him (though, to be honest, he's never happy), vowing to exact vengeance on Sonic and his friends.
In the Village Center, Knuckles is telling Tails a bartender joke when Shadow blindsides (sorry, pummels) Knuckles into a wall, with Eggman and his Spy Bots returning to watch the action and capture it from multiple angles, respectively; Eggman commentates throughout on how well certain aspects of the fight will translate into his game. Shadow continues to attack the two Team Sonic members relentlessly, tricking Knuckles into accidentally punching Tails out of the fight with a well-timed teleport and then beating the echidna to a pulp as he realizes his error. Amy and Sticks arrive and attempt to fight him as well, but are also easily dispatched when Shadow snatches them from behind, lifts them into the air, and callously tosses them aside like yesterday's garbage to plummet to the ground; obviously, the landing is not soft, and it leaves Amy with barely enough strength to activate her Communicator and weakly call Sonic for aid before she collapses.
With concern a likely factor, Sonic's on the scene almost immediately, and he's horrified to find his friends in excruciating pain and struggling to get to their feet. Confused and worried, his mind races as he wonders what could have happened to inflict such agony upon them. And then his burning questions are answered as he spots the culprit: Shadow, floating to the ground and saying it's about time the "slowpoke" arrived. Sonic, not pleased that his dark counterpart has curb-stomped his pals, asks what he's done, but only gets a shoulder charge from Shadow in response, the strength of the blow causing him to fly through three trees and into the village wall. Part One ends with Shadow standing ominously over a stunned Sonic as he lies in the rubble, once again on the verge of finishing him off and settling the score once and for all (and an annoyed Knuckles bemoans the cliffhanger ending, as is tradition by now). One thing's for sure: Sonic and company ain't walking away from this fight unscathed.
This episode provides examples of:
- Deadly Dodging: During Shadow's (brief) tussle with Tails and Knuckles, the former attempts to surprise-attack Shadow from behind as he focuses on the latter. Unfortunately, Shadow notices, and as Knuckles throws a punch, he teleports away at the last moment, causing the punch to connect with Tails instead; the fox is incapacitated by the blow, and Knuckles follows him shortly after realizing he screwed up.
- Manipulative Editing: Eggman edits an interview with Sonic he recorded in order to make it sound like he's trash-talking Shadow. When the edited footage is shown to Sonic's dark doppelganger, it's painfully obvious that it's been manipulated, but funnily enough, Shadow, of all people, still falls for the ruse.Sonic: Shadow?-he is-weak-that-wind-bag-could-never-beat-me.-What a-weak-weak-weak-wind-bag-he is.Shadow: This aggression shall not stand. Sonic and his friends shall pay!
- No-Holds-Barred Beatdown: After being tricked into thinking Sonic insulted him, Shadow ambushes Team Sonic out of vengeance and utterly destroys them in what is perhaps the most vicious display of violence they've ever received in the series. What drives the point home is that, in an unusual depiction of injuries for Boom, Sonic's friends are shown having difficulty in getting back up after the beating with clear expressions of agonizing pain on their faces. Even though Sonic fares significantly better, managing to fight Shadow on even ground for awhile at the beginning of Part 2, he still gets roughed up a fair bit, and they're all still feeling the injuries by the middle of that episode, long after the fight is over. Shadow does not play around.
- Pre Ass Kicking One Liner: Shadow delivers a brutal one to Tails before the big fight scene.Tails: Shadow? What are you doing here?Shadow: Fox hunting.
- Roadside Wave: Eggman gets splashed with mud when Sonic drives over a puddle. Sonic apologizes and even allows Eggman to do the same to him, so Eggman jumps in the puddle, which doesn't splash Sonic at all.
- When Tommy Thunder's new video game comes out, Wild Cat says, "Shut up and take my money!".
- When Eggman tries to advertise his new 'Stache Smash video game, he asks Tails, Knuckles, and Mark what the newest, coolest video game is. Tails and Knuckles respectively guess Super Plumber Bros. and Mortal Bloodsport VII.