"Operation: S.I.T.T.E.R." "S.I.T.T.E.R." stands for "Sweetheart's Involvement Transforms The Evening's Reality." Cree is hired by Mrs. Gilligan to watch over Hoagie and Tommy for the night."Operation: S.A.T.U.R.N." "S.A.T.U.R.N." stands for "Stuff Abducted Turns Up Revolving Nowhere." All of the Earth's Rainbow Monkey dolls are abducted by an early model named Ramon 4, who was rejected and unloved.
"Operation: T.R.I.C.K.Y." "T.R.I.C.K.Y." stands for "Trivial Rival Instigates Candy Krazy Yearnings." Numbuh 4's candy is stolen by Stickybeard while he is trick-or-treating."Operation: U.N.C.O.O.L." "U.N.C.O.O.L." stands for "Undead's Nocturnal Craving Overtakes Operative's Love." The Kids Next Door assist Numbuh 42 in recovering the captured Numbuh 78, who was kidnapped by zombies.
"Operation: P.R.E.S.I.D.E.N.T." "P.R.E.S.I.D.E.N.T." stands for "Protection Requires Extreme Skill Involving Democratically Elected Notable's Transportation.
"Operation: S.P.R.O.U.T." "S.P.R.O.U.T." stands for "Sickening Produce Removal Operation Ultra Tricky." Numbuh 4 accidentally eats a Brussels sprout and has to undergo an emergency operation by the Kids Next Door to remove it before digestion takes place.
"Operation: R.A.B.B.I.T." "R.A.B.B.I.T." stands for "Rescue Aid Beloved Bunny In Trouble." When the second grade's pet bunny is stolen, Numbuhs 2 and 5 agree to help recover it."Operation: F.L.U.S.H." "F.L.U.S.H." stands for "Foolish Loser Undoes Sinister Hopes." The enemies of the Kids Next Door set into motion a plan to take over the children's treehouse. But the Toilenator ruins their plans.
"Operation F.O.O.D.F.I.T.E." "F.O.O.D.F.I.T.E." stands for "Fiendish Old Ogre's Disgusting Food Is Thrown Everywhere." The Kids Next Door must survive the school cafeteria cuisine of Gramma Stuffum."Operation C.L.U.E.S." "C.L.U.E.S." stands for "Cutlery's Location Uncovers Elementary Solution." Numbuh 2's mother tries to impress Numbuh 3's parents during a Sunday dinner,
"Operation: N.U.G.G.E.T." "N.U.G.G.E.T." stands for "Numbuh Uncovers Glistening Golden Edible Treat." Numbuh 4 finds the chicken nugget motherlode, bringing on a new "chicken rush.""Operation: M.A.C.A.R.R.O.N.I." "M.A.C.A.R.R.O.N.I." stands for Museum's Artwork Cruelly And Recklessly Ripped Off Nearly Impossibly." The Kids Next Door initiate a prisoner exchange with the adults at the mall, but are upset that the child is Numbuh 13.
"Operation: P.O.O.L." "P.O.O.L." stands for "Prevent Opposite Operative's Larceny." Numbuh 4 gets a new pool at his house, but can't swim. But things get even worse when a Lizzie from a parallel dimension kidnaps Numbuh 1 through a dimension portal in the pool.
"Operation: C.A.K.E.D.-F.O.U.R." "C.A.K.E.D.-F.O.U.R." stands for "Children's Annual Kompetition Exposes Devilishly Fiendish Operation Up River." The competitive Kids Next Door battle it out on the water to win an annual innertube competition which Hoagie always loses.
"Operation: C.H.O.C.O.L.A.T.E." "C.H.O.C.O.L.A.T.E." stands for "Candy Hunting Operative's Chocolotized Opponent Literally A Touchy Enemy." Numbuh 5's family and the Kids Next Door are attacked by Heinrich, who wants revenge on Numbuh 5."Operation: M.A.T.A.D.O.R." "M.A.T.A.D.O.R." stands for "Misbehaving Agent Teases Adults During Organized Recreation." Numbuh 4 must decide between becoming a matador and going on a mission.
"Operation: L.U.N.C.H." "L.U.N.C.H." stands for "Lizzie Underappreciates Nigel's Chowtime Hardworkingness." Lizzie forbids Nigel from working with a Robin Hood-like thief steals the lunch she brought especially for both of them.
"Operation: K.N.O.T." "K.N.O.T." stands for "Kids' Necks Overwhelmingly Tied." Numbah 1 tries to rid his school of wearing ties by going to wear ties are created."Operation C.L.O.S.E.T." "C.L.O.S.E.T." stands for "Child Lost On Seriously Elevated Tundra." The Kids Next Door are called to rescue a child trapped under an avalanche of clothes from a closet.
"Operation: S.N.O.W.I.N.G." "S.N.O.W.I.N.G." stands for "Sickly Nigel Opposes Warped Incumbent's Nasty Grasp." Numbuh 1 is given a cold by the 4th Grade Class President as part of a scheme during "snow day" to retain his presidential power.
"Codename: M.A.U.R.I.C.E." "M.A.U.R.I.C.E." stands for "Mature Agent Undergoes Reprogramming Into Childhood's Enemy." Numbuh 5 tries to stop the teenagers from reprogramming her mentor Maurice into an enemy of the Kids Next Door.
"Operation: L.O.V.E." "L.O.V.E." stands for "Little Operative Very Emotional." Numbuh 3's chances to sing a solo in the school musical are dashed when the Delightful Children Down the Lane ruin the play."Operation: C.O.U.C.H." "C.O.U.C.H." stands for "Creepy Otherworld Under Cushiony Heap." Numbuh 4 gets sucked into the couch when Numbuh 3 loses the remote control for the television under the cushions.
"Operation: D.O.D.G.E.B.A.L.L." "D.O.D.G.E.B.A.L.L." stands for "Dangerous Old Dude's Game Excellently Beats All Little Losers." The Dodgeball Wizard, an adult in his sixties, challenges Numbuh 4 to a duel so he can prove he is the world's best dodgeball player.