52 episodesFirst aired 11 September 2010
Sept 201022m
Coop falls for Old Lady Munson’s niece Fiona, and Kat does everything he can to make Coop look bad.
Sept 201022m
When Millie tickles Mr. Kat's 'tickle spot' he goes into a blissful state that renders him useless as an alien agent and when Kat's empire find out about him they send a robot to destroy Millie.
Sept 201022m
Kat's swarm of flea-sized mind control robots hop into the ears of the people of Bootsville and soon they all destroy Coop.
Oct 201022m
With Coop out of town, Kat wants to turn water into milk and Dennis comes to the rescue.
Oct 201022m
Millie brings home the class hamster, unaware that Mr. Kat hates hamsters.
Oct 201022m
When Kat uses his growth ray to bury Bootsville in a catnip jungle, Coop is blamed by the irate Bootsville Gardening Club.
Oct 201022m
Coop tries to stop the destruction of Massive Mart.
Nov 201022m
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!
Nov 201022m
Coop and Dennis climb inside Kat's scratching post and discover Kat's alien technology has created an infinity within.
Nov 201022m
Coop, Millie, and Dad are taken away to a top secret base to be interrogated, after a UFO investigator suspects they are aliens.
Nov 201022m
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.
E12Dec 201022m
Due to an ‘over-loading’ problem on the Kat Nebula, Kat plots to turn Bootsville Beach into a giant litter box.
E13Dec 201022m
Kat’s devious magnifier satellite is causing a dangerous heat wave in Bootsville.
E14Apr 201122m
Coop and Dennis compete with one another to reduce their carbon footprints.
E15Mar 201130m
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.
E16Mar 201122m
Coop tries to undo the Kat invasion, which he brought about by fooling with Kat’s time machine.
E17Mar 201122m
Coop becomes Dennis’ wing-man for a change, as they go in search of the 'sewer-croc-baby'.
E18Apr 201122m
Coop breaks every window in Dennis' house, and is forced to work off his debt by working in Henry's store.
E19Apr 201122m
Growler swallows a Kat device which makes him grow to the size of a T-Rex.
E20Apr 201122m
Kat's malfunctioning spybot thinks Coop is its new master, and wants to protect him from Kat.
E21Apr 201122m
The Kat Kommander's rebellious son runs away to Earth, where he becomes a handful for Kat, and a danger to the human race.
E22Apr 201122m
Dad accidentally swaps an assortment of Kat's weapons to the unwitting residents of Bootsville.
E23May 201122m
Kat is left at a kennel while the Burtonburgers go on vacation.
E24May 201122m
Kat becomes obsessed with making the biggest yarn ball ever made, and starts rustling sheep to gather their wool.
E25May 201122m
Dennis is accidentally knocked into a portal around the world.
E26Jun 201122m
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.
E27Jun 201130m
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.
E28Jun 201130m
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.
E29Jun 201130m
Old Lady Munson's garden gnomes come to life and mistake Coop as their leader.
E30Jul 201130m
Old Lady Munson tells Millie creative stories about her adventures in the past.
E31Jul 201130m
The evil alien hamster Mr. Cheeks comes back to get revenge on his nemesis, Kat.
E32Jul 201130m
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 is trying to enjoy a virtual picnic in a secluded spot with his girlfriend, but the kids and Coop keep crashing Coop's birthday.
E33Jul 201130m
Dad orders Coop to spend more quality time with his little sister; Kat builds a telepathy helmet.
E34Jul 201130m
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!
E35Aug 201130m
Coop and Kat fight over the animal's new lightning box generator and end up swapping brains.
E36Aug 201130m
Coop discovers buried treasure under Old Lady Munson's house.
E37Aug 201130m
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.
E38Aug 201130m
Kat builds a device that brings an assortment of movie monsters to life.
E39Sept 201130m
Coop and Dennis battle Kat's army of living hairballs.
E40Sept 201130m
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.
E41Sept 201130m
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.
E42Sept 201130m
Kat turns Coop into a cave man, hoping his lowered I.Q. will make him easier to outsmart. Now Dennis must change Coop back to human.
E43Oct 201130m
Coop takes on the teen aged bully who pedals the Curly Swirl Ice Cream cart, and forgets to pay attention to Kat's latest evil plans.
E44Oct 201130m
Kat makes himself a high-powered good luck charm, which means bad luck for Coop.
E45Oct 201130m
Buck Diamond, Animal Protection Officer declares Coop "Bootsville's Most Wanted".
E46Oct 201130m
Coop and Fiona have to settle their argument before they can work together to stop Kat in his evil tracks.
E47Oct 201130m
Kat and Old Lady Munson show up at school where they work together to make Coop's life miserable.
E48Nov 201130m
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.
E49Nov 201130m
Kat thinks the haunted LeBoot Mansion will be the perfect place for an inter-space teleporter.
E50Nov 201130m
Kat controls the mind of Agent Napolitan, but his plan backfires when some squirrels attack him.
E51Nov 201130m
When Kat is fired 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 the Kat Planet.
E52Dec 201130m
Coop and the rest of the kids need Kat's help to escape Kat Planet. Will he give it?