"Ill Suited" is the sixty-sixth episode of Kim Possible, and the first episode of the show's fourth and final season. As such, it is the first episode that takes place after the events of Kim Possible Movie: So the Drama.
The episode seemingly begins right at the end of So the Drama, where Kim and Ron are dancing at their high school prom. After they kiss, Kim smiles at Ron. Her smile then turns into a wicked grin before she dissolves into a mass of green sludge and reveals herself to be a Synthodrone. Ron freaks out at this and jerks awake, screaming. Rufus also wakes up from the noise and hushes Ron, pointing out that it is 3 o'clock in the morning. Ron now panicking, grabs his phone and calls Kim, asking her if she really is a Synthrodrone. Kim reassures him, telling him that he was having a nightmare and is about to hang up but Ron also asks her if she and him really kissed - to which Kim confirms they did but she also tells him it will not happen again if he continues to call in the middle of the night. After both hanging up, Ron lies in bed and notes how “love is complicated.”
Later on, they both set to foil Professor Dementor’s latest plot, catching him in an underground lab. When Ron mentions that he is now Kim’s boyfriend, Dementor fails to believe him, despite him insisting that it‘s true. Dementor wonders how Kim managed to find him and Kim pulls out the to-do list that he dropped while he stole the ultrasonic drill, taunting him for making the job of finding him “that much easier“. Ron reads out the list, reminding Dementor that one of his “to-dos” was to call his mother. Kim tells him that he can call her from prison. Dementor simply says that he’ll add one more thing to his list -- to eliminate Kim Possible, and fires up the stolen drill. She shields the attack (and Ron) with her battle-suit and jumps up to the platform Dementor is on, ready to apprehend him. Before she’s able to however, Dementor (surprised at Kim’s enhanced abilities) asks her when had she gained her new battle-suit. Ron tells him that the suit is new, and Kim adds that it is indestructible. Dementor then sets his henchmen on Kim and aims the drill at Ron. Kim easily takes out the henchmen, leaving Dementor to resort to using a ray gun on her instead. She catches the blast with the battle suit and returns the projectile, knocking the gun out of Dementor’s hand to his frustration. Ron calls to Kim for help, giving Dementor the opportunity to escape. She shuts off the ultrasonic drill and rushes to see if her “so-called” boyfriend is okay.
When they're at school, Ron and Monique both express happiness at how they're now finally seniors. Kim's not so enthusiastic--she explains that while she is happy about finally being a senior, she admits that she's still kind of bummed about Dementor getting away (especially since it was her and Ron's first mission as high school seniors. Ron helps her feel better about what happened, but then Bonnie comes up to them and obnoxiously asks if Kim and Ron are still dating. Kim confirms that Ron is still her boyfriend and Bonnie tries convincing Kim to break up with Ron and start dating a jock--Bonnie's reasoning for this is that she feels that it's practically "like a rule" for cheerleaders to date jocks, especially since they are seniors. Kim dismisses this and after Bonnie leaves and Kim has to go to class, she tells Ron not to obsess over what Bonnie said. However, throughout the day Ron does obsess over the idea and into the next day--however, just as he convinces himself that he and Kim live in a "trade-up free zone," he overhears Kim talking with Monique about how she actually agrees with Bonnie about "trading up." Just after Ron runs away from this, it turns out that Kim and Monique were actually talking about Monique trading up her current cellphone for a newer one. Ron then decides that either Kim should not be a cheerleader or that he needs to be a jock. Seeing a poster for the football team, Ron tries out for the position of the school’s new quarterback.
The coach, Mr. Barkin, doubts that Ron is quarterback material with the name “Stoppable” but Ron insists he can make the cut. He quickly gets on Barkin’s bad side during practice and Barkin orders him to crabwalk a lap where he comes across Kim and Monique. When he tells them he is practising for the football team, Kim immediately suspects that it is because of Bonnie’s trash talk from earlier. Ron denies this, instead saying he is doing it for college. Kim then gets a call from Wade, but all she gets for her newest sitch are GPS coordinates from a strange old lady. The lady’s cat, Princess, is stuck in a tree. Ron attempts to save the cat, but she attacks him and sends him back down covered in cuts, so Ron instead suggests that Kim try saving her as she is wearing her battle-suit anyways. Kim quickly leaps up the tree and encourages Princess into her arms. Unbeknownst to Kim, Princess is not all she seems.
After rescuing her cat, the old woman insists that they be thanked properly and invites them into her house for some cookies. While she is in the kitchen, Kim and Ron note how strange and even creepy the woman is (including her ornaments and other collectibles), choosing to have the cookies 'to go'. Princess then suddenly jumps from Kim’s arms and fires a beam at her. Narrowly dodging and now alerted that they have been set up, Princess able to analyse Kim’s battle-suit. Before Kim or Ron can react, all the exits in the house are locked down with metal slabs and the old lady reveals 'her' true identity as Professor Dementor.
Ron mocks Dementor for wearing a dress, but Dementor insists that it is a housecoat. He quickly tries of the argument and orders his collectibles to attack the two. The collectibles throw plates and fire hard candies at them while Kim tries to repel them with her battle-suit. As she is about to counterattack, she is stopped by the sofa (actually one of Dementor's contraptions) which quickly pulls her to the ground and swallows her. Dementor laughs in triumph at the apparent end of the teenaged heroine when the sofa begins to expand. Kim bursts through the sofa using the battle suit's shielding, sending parts of the sofa flying across the room and destroying the remaining attack collectables. She then goes for Dementor who simply grabs the data collected by the electronic cat and tosses it to Kim, who catches the now disabled machine. He then escapes through a cupboard fashioned into a rocket, leaving Kim and Ron with the cat which. After a moment, the two notice that the cat is counting down in a self-destruct sequence. Kim hastily grabs Ron and they both make their own escape through the hole in the roof. Seconds after landing, the house and all its contents are vaporized by the self-destruct sequence. Kim calls up Wade and tells him that Dementor had the “home field advantage”, inspiring Ron to try and “secretly borrow” Kim’s suit.
The next night, Ron sneaks into Kim’s bedroom while she is out babysitting and takes her battle-suit to wear to football practice. With the suit underneath his uniform, Ron has another try at getting on the football team. The suit naturally gives him incredible strength and speed, easily landing him as Middleton’s new quarterback and becoming a hero in his first match - astonishing everyone from Mr. Barkin to Kim and the rest of the cheer squad. Bonnie finds Ron’s new skills to be too good to be true, and although she seems jealous at Ron for stepping-up, even Kim can't help but be suspicious about Ron's sudden improvement.
After the game, Kim and Ron celebrate at Bueno Nacho. When Kim expresses her doubts about Ron‘s newfound abilities, he just tells her how, like herself, he is full of surprises. Professor Dementor then busts in through the roof of the restaurant. After some banter, he reveals the results of his analysis of the battle-suit, a magnetic controller, and attempts to take control of Kim using her battle-suit. He instead takes control of Ron, who is still wearing the suit under his uniform. Both Kim and Dementor take a few moments to catch on that something is not right, with Kim realizing that Ron was wearing it right before Dementor activates the shield on the suit. This destroys Ron's clothes and reveals to Kim the true source of Ron's sudden football skills. Dementor then controls Ron to attack Kim, during which Ron explains why he stole the suit in the first place. Kim, initially angry at Ron for stealing her stuff, lying to her and cheating his way onto the football team, Ron explains why he did it: he overheard her and Monique's conversation about "trading up" and he didn't want to risk losing her to someone else. Hearing this, Kim explains that she and Monique were talking about Monique's cellphone. Ultimately, Kim assures Ron that she doesn't care that he's not a jock and that she cares about him for who he is. Just as Ron's finishing his apologies to her, he throws Kim into the back of the restaurant - rendering her unconscious. Dementor releases Ron from the suit to put it on himself, intending to destroy Kim Possible with his own hands. Rufus signals for Ron to toss him over to Dementor’s control panel so he can stop him. Rufus, able to control of the suit himself, forces Dementor to repeatedly punch himself. Ron immediately makes his way over to Kim and helps her up and they both watch as Dementor hits himself over and over again.
On his second match, Ron (now without the aid of Kim's battle-suit) uses his "mad running away skills" honed through years of going on missions with Kim to dodge the opposing team's merciless attacks and score and beats the all-time rushing record, and ultimately wins the game. Later on, Ron (off-screen) confesses to Mr. Barkin about cheating his way onto the football team, which Kim is proud of her boyfriend for doing. However, Mr. Barkin comes up to the couple and tells Ron that he can still be part of the football team, albeit as the new running back instead of the quarterback, cementing Ron's newfound status as a jock. Ron's excited about this, but Mr. Barkin punishes Ron for cheating his way onto the team into the first place by making him crabwalk laps around the football field.
- In the show's airing order, this is the only season premiere in which Dr. Drakken and Shego do not appear.
- During the tryouts for the football team after being reminded of an incidient referred to as "The chess club incident", Ron sternly says the phrase: "The first rule of chess club is: you do not talk about chess club". A reference to the book/movie Fight Club.
- At the end of the episode, Ron asks Kim if she had ever water-skied over a shark, referencing the phrase "Jumping the Shark", which was derived from an episode of the sitcom Happy Days.
- This is the second of two occurrences where Kim's cheerleader uniform comes up to reveal her cheerleading spankies, which (despite some assertions) are not Kim's underwear.
- The new season with the beginning of Kim and Ron's senior year with no explanation as to what happened in the interim, a span of about three months from Junior Prom.
- Though more of an arguement, Ron notes he and Kim had the first fight of their relationship.
- The plate that Dementor threw towards Ron hits the wall and cuts one of the curtains. In all scenes after that, the plate is missing from the wall.
- Princess' coat markings are inconsistent throughout the time she is on screen.
- When Ron is wearing Kim's battle-suit, he is not wearing the leg pouch that Kim usually wears on her right leg. When Dementor steals the suit however, the leg pouch can suddenly be seen. The same occurs with the battle-suit's gloves.
- At the beginning of the episode, the Middleton High readerboard reads "Not the End", an immediate reference to the end of So the Drama when the readerboard read "The End" originally signifying the end of the series.
- Other references to So the Drama include Ron's dream when he and Kim were at the prom and when Kim melts, making Ron think she is a Synthodrone like Eric and calling her afterward to ask her if she is or not.