"Let the Games Begin": Coop discovers his life will never be the same again when his spoiled little sister, Millie, brings home an alien cat and Coop blows up his collar.

"Night of the Zombie Kat": Coop watches a horror movie, then after, Kat uses flour to make his skin white and scare Coop.

"Trespassers Will Be Persecuted": Old Lady Munson lays down the law: Coop is not to set foot into her yard, but Kat makes sure he crosses the line again, again, and again.

"Me-Oh Me-Oh Meow": After meowing too much, Kat is forced to wear a special collar, but in the end Kat straps the collar onto Coop's foot.

"Do Not Fort Sake Me": Coop and Dennis build a tree fort in the backyard. Kat, taking advantage of how tall the fort is, uses it to power up his collar and start communicating with other "Kats".

"Cookie D'Uh": Coop gets accused of stealing cookies.

"Nip/Duck": Coop is determined to expose the truth about Kat by showing his X-rays to Dad and Millie.

"Search and De-Toy": Coop comes up with a plan to rescue his dad's (possibly his) toy helicopter from Old Lady Munson.

"Flu the Coop": Tensions mount when Coop is sick and Kat is none too pleased because his germs irritate Kat's skin.

"Class Act": Coop finds a magic kit in the House of Swap and uses it to do a magic act to make Kat disappear forever.

"Hypnokat": Kat's new toy mouse hypnotizes the other cats in the neighborhood, and Kat seizes the opportunity to create his own cat army.

"The Allergy": Coop convinces Dad that he's allergic to Kat so Dad will get rid of the pesky feline for good. Kat turns the tables on Coop, convincing Dad that he's allergic to Coop as well!

"Just Me and Glue": When Coop and Kat get glued hand to paw, they are forced to spend the day together. Kat turns out to be a big help in putting together Coop's new Mechanizor Warrior model robot until Coop realizes Kat has programmed it to destroy Coop, but Kat will also be destroyed.

"You'll Be Show Sorry": When a contest for pets is announced in Bootsville, Coop subscribes Kat because the winner wins a trip around the world. However, Coop regrets this when he realizes he will be taking the trip with Kat if he wins.

"How the Test Was Won": As Coop prepares for a big test, Kat comes up with multiple ways to distract him from studying, which in the end, Kat ironically helps Coop remember the things he should study thus having a B+ on the test.

"I'm Okay, You're a Kat": Coop discovers a self-help motivational tape in the House of Swap and turns his life around by listening to it while he sleeps, until Kat messes with the tape to make it say bad things to him instead. Now it's up to Coop to use the tapes to fight evil Kat with an even more evil Coop!

"Dial "B" for Babysitter": Coop has his work cut out for him when he's forced to babysit Kat, Old Lady Munson, and her dog Growler.

"The Grass is Always Meaner": Coop comes up with a plan to make money for a Captain Blasteroid Helmet by cutting Old Lady Munson's lawn; Kat tries to stop Coop and Dennis by making the grass grow.

"One Big, Happy Family": Coop and his family take a family photo at the House of Swap, but Kat tries to make Coop look bad.

"Happy Campers": Dad competes with Dennis' father as to who's the best camper during a family weekend in the woods. Coop and Dennis use their knowledge of the forest to lead Kat into escalating confrontations with nature.

"U.F. Float": Bootsville's annual parade has a Spaced Out theme this year and Dad wants to advertise the House of Swap with a Flying Saucer float.

"Play N'Ice": Dad builds an ice palace and rink in the backyard during a snowy day. Meanwhile, Coop tries to find a way into Kat's secret base.

"House of Scream": Kat takes advantage of Dad turning the House of Swap into a horror fun house by going for real blood.

"Planter's Warp": Kat uses his alien technology to turn the plants in the backyard into monsters.

"Curse of Tutankitty's Tomb": Egyptian artifacts at the museum turn out to be high-tech relics from Kat's world.

"Pet Peeved": When Millie finds a new school friend exactly like her named Molly, she starts to ignore Kat, causing Kat to run away.

"Don't Give Me No Static": Desperate for a completed science project, Coop borrows one of Kat's weird machines without knowing what it does.

"Storm Drained": Coop is determined to have Bootsville win against Timber Lane in a baseball game.

"Fishy Frisky Business": On a family shopping trip, Kat gets Coop banned from the grocery store.

"Teed Off": Dennis and Coop's fathers encourage them to revive a neighborhood tradition, the "round the block" golf challenge.

"Something Fishy in Owl Lake": The Burtonburgers face friends, neighbours, and each other in a local fishing derby.

"Dire Education": Dad comes to school to shadow the kids on Parents' Day; Millie takes Kat to show-and-tell.

"Crouching Cooper, Hidden Kat": When Kat and Millie embarrass Coop in front of the school by flipping him, he turns to Dennis for martial arts lessons.

"Tom-Kat Foolery": Coop's April Fool's Day jokes have the entire town not believing a word he says, so how can Coop stop what seems to be a Kat-led UFO invasion when even Dennis assumes it to be Coop's biggest joke yet?

"In Dog We Trust": Seeing how freaked out Kat gets by a huge stray dog, Coop adopts it as his pet and bodyguard, but the dog is a lot more responsibility than he thought, especially after Coop's plan backfires, as Kat retrains it to destroy the house.

"Catch My Drift": Kat overcomes his fear of snow to make sure Coop gets chilly in the Demolition Run toboggan challenge.

"Suddenly Last Slammer": The police and Old Lady Munson accuse Coop and his friends of "waking the neighborhood".

"The Kitty Vanishes": Kat struggles to perfect a teleporter to steal and transfer seemingly unimportant items across space to his home.

"Capture the Kat": Kat wants a day off, but Coop and the gang play capture the flag right through to his secret forest oasis.

"Outer Space Case": When Old Lady Munson shows an unusual interest in Coop and Dennis' favorite show, they become equally obsessed with finding out why she likes it.

"Buzz Off!": It's time for the annual Bootsville Day festival celebrating the town's founding. After Kat sees how much the mosquitoes annoy everyone, he uses his alien technology to make them grow huge!

"Fat Kat": Kat becomes fat after eating too much human food when he sends all of his cat food to his home planet. When he becomes too fat to attack Coop, Coop must keep him fat.

"Kat Whisperer": After Coop uses cat whispering to make Kat into his new best friend, he becomes a pal to all animals.

"Bend It Like Burtonburger": Coop and Dennis join the soccer team but Coop would rather show off than use teamwork.

"Stall That Jazz": When Kat's listening transmitter becomes lodged in his ear, his hearing becomes super sensitive.

"Under Destruction": After Kat's latest tantrum almost destroys the house, Dad starts his own extreme renovation.

"Beware the Were-Coop": After Kat scratches Coop under a full moon of Halloween, Dennis believes that Coop is turning into a werecat.

"Trick or Threat": On Halloween, Coop and Dennis plan on trick or treating...much to Kat's liking, as he tries to communicate with his home planet, Kat Nebula.

"Hack Kattack": Kat's attempts to hack satellites for a mind control broadcast are given a leg up by Dennis' new universal remote control and satellite dish.

"It's a Rocket, Man": Coop joins the Bootsville Rocket Club and with a little secret help from Kat, he's soon the star member, but when Coop learns Kat is going to use his rocket to destroy a satellite, the only way Coop can stop him is to destroy his own record breaking flight.

Coop's hopes of a normal Christmas are shattered by the fact that Kat is constantly getting him in trouble; it is revealed that Kat really misses his family back at his home planet. Coop and Millie's grandparents are expected to visit for the Christmas, but many troubles cause them to be late.

"Something About Fiona": Coop falls for Old Lady Munson's niece Fiona, and Kat does everything he can to make Coop look bad.

"Tickled Pink": When Millie tickles Mr. Kat's "tickle spot", he goes into a blissful state that renders him helpless as an alien invader. When Kat's empire find out about this, they send a robot to destroy Millie.

"Flea Brains": Kat's swarm of flea-sized mind control robots hop into the ears of the people of Bootsville and soon they all want to destroy Coop.

"Menace the Dennis": With Coop out of town, Kat wants to turn water into milk and Dennis comes to the rescue.

"Cheeks of Evil": Millie brings home the class hamster, unaware that Mr. Kat hates hamsters.

"Reap It and Weep": When Kat uses his growth ray to bury Bootsville in a catnip jungle, Coop is blamed by the irate Bootsville Gardening Club.

"Blasteroid Blues": Coop tries to stop the destruction of Massive Mart.

"Rat-a-Phooey": Kat builds a Rat-ray gun, which he plans on using to turn Coop into a rat, but Dad gets zapped instead, so Coop hopes he can change Dad back... If he can catch him first!

"Trash Talking": Coop and Dennis climb inside Kat's scratching post and discover Kat's alien technology has created an infinity within. While they are inside, the scratching post gets taken to the dump.

"Over the Radar": Coop, Millie, and Dad are taken away to a top secret base to be interrogated, after a UFO investigator suspects they are aliens.

"Nuff Said": After taking the fall for one too many of Kat's destructive escapades, Coop decides to let Kat have free rein to cause whatever destruction he wants.

"Rhymes with Coop": Due to an "over-loading" problem on Kat Nebula, Kat plots to turn Bootsville Beach into a giant litter box.

"Bringin' the Heat": Kat’s devious magnifier satellite is causing a dangerous heat wave in Bootsville.

"The Three Aarghs": Coop and Dennis compete with one another to reduce their carbon footprints.

"Kat to the Future Part One": Coop uses Kat's time machine to go back to the past and stop Millie from bringing Kat home, but ends up altering the future for the worse.

"Kat to the Future Part Two": Coop tries to undo the Kat invasion, which he brought about by fooling with Kat's time machine.

"Down the Drain": Coop becomes Dennis' wingman for a change, as they go in search of a "sewer-croc-baby".

"9 to 5 to Oblivion": Coop breaks every window in Dennis' house, and is forced to work off his debt by working in Henry's store.

"When Bad Dogs Go Big": Growler swallows a Kat device which makes him grow to the size of a T-Rex.

"The Bottyguard": Kat's malfunctioning spybot thinks Coop is its new master, and wants to protect him from Kat.

"Rebel with a Claw": The Kat Kommander's rebellious son runs away to Earth, where he becomes a handful for Kat, and a danger to the human race.

"Swap Wrecked": Dad accidentally swaps an assortment of Kat's weapons to the unwitting residents of Bootsville.

"Hit the Road": Kat is left at a kennel while the Burtonburgers go on vacation.

"Never Cry Sheep": Kat becomes obsessed with making the biggest yarn ball ever made, and starts rustling sheep to gather their wool.

"Kickin' Butler": Dennis is accidentally knocked into a portal that sends him on a wild trip around the world. If Coop wants Kat to fix the device and bring Dennis back, Coop must be Kat's servant.

"You Kat See Me": Kat makes himself invisible and causes trouble for Coop on the night he invites Fiona to dinner and when Dad invites Coop's teacher over for dinner.

"Keep on Rockin'": Coop's grandparents visit, so Dad buys them rocking chairs. However, it turns out they are adventure junkies who accept that Kat is an alien.

"It's in the Bag": Coop searches for the last available bag of the feline's favorite food after the factory that makes it closes down so he can taunt Kat.

"King of the Pipsqueaks": Old Lady Munson's garden gnomes come to life and mistake Coop as their leader.

"Down the Creek": Old Lady Munson tells Millie creative stories about her adventures in the past.

"Turn the Other Cheeks": The evil alien hamster Mr. Cheeks comes back to get revenge on his nemesis, Kat.

"Birthday Bashed": Coop's birthday is here, and everyone is coming to his party, and Phoebe is trying to get rid of Fiona so she can have Coop to herself. Meanwhile, Kat tries to enjoy a virtual picnic in a secluded spot with his girlfriend, but the kids and Coop keep interfering.

"Mind Games": Dad orders Coop to spend more quality time with Millie. Meanwhile Kat builds a telekinetic helmet, which Millie unknowingly takes control of.

"Strange Kat on a Train": Coop goes on a train to buy something from a man named Old Herman, Unfortunately it turns out to be the evil alien hamster, Mr. Cheeks!

"Board Kat": Coop and Kat fight over Kat's new lightning box generator and end up switching bodies.

"The Treasure of Sierra Munson": Coop discovers buried treasure under Old Lady Munson's house.

"Fangs for the Memories": Kat's memory eraser leads to Coop forgetting Kat is an evil alien, but Dad accidentally gets Coop's lost memories and suddenly knows the terrible truth.

"Drive-In Me Crazy": At a drive-in theater, Kat builds a device that brings an assortment of movie monsters to life.

"Hair Brains": Coop and Dennis battle Kat's army of living hairballs.

"Hot Dog Day": It's Hot Dog Day, and Coop has the honor of being named Keeper of the Weiner Water. But Kat wants to ruin the most special day of the year.

"Amazing Feet of Strength": Kat soups up Coop's new soccer shoes to allow the wearer to run faster and jump higher, and Coop wears the shoes in the championship game.

"Me Coop, You Kat": Kat turns Coop into a caveman, hoping his lowered intelligence will make him easier to outsmart. Now Dennis must change Coop back to normal.

"You Scream, I Scream": Coop takes on the teenage bully who pedals the Curly Swirl Ice Cream cart, and forgets to pay attention to Kat's latest evil plans.

"Good Luck Harm": Kat makes himself a high-powered good luck charm, which means bad luck for Coop.

"Bootsville's Most Wanted": Buck Diamond, an Animal Protection Officer, declares Coop "Bootsville's Most Wanted".

"Kat of Diamonds": Coop and Fiona have to settle their argument before they can work together to stop Kat in his evil tracks when he steals a valuable diamond.

"Coop D'Etat": Kat and Old Lady Munson show up at school where they work together to make Coop's life miserable.

"The Incredible Shrinking Coop": Kat shrinks Coop and Dennis down to size and tries to squash them like bugs, which makes it hard for Coop to do something big for Dad for Father's Day.

"Who's Haunting Who?": Kat thinks the haunted LeBoot Mansion will be the perfect place to build an inter-space teleporter.

"It's All in Your Head": Kat tries to control the mind of Agent Neapolitan to sabotage a new satellite defense system, but his plan backfires when squirrels attack him.

"The Kat Went Back Part One": When Kat is replaced for incompetence, the Robo-Kat-Kops that are sent to take him home also capture Coop, Dennis, Fiona, Millie, Lorne, and Harley and take them to Kat Nebula.

"The Kat Went Back Part Two": Coop and the rest of the kids need Kat's help to escape Kat Nebula. Will he give it?