I don't wanna ruin her life. She should have the same opportunity to ruin her life that I have.
K.C. to Kira and Craig

The Domino Effect is the twentieth episode in Season 3 of K.C. Undercover and the seventy-first overall. It first aired on January 29, 2018 to 0.88 million viewers.[1]


The Coopers track down agents who are distributing weapons to enemy agencies, only to discover they are parents of K.C.'s classmate Amy.[2]


Main Cast

Recurring Cast

Guest Cast


To view the The Domino Effect gallery, click here.


  • This is the first episode of the four-part "Domino Effect" arc.
  • It was revealed that K.C. and Amy have known each other since the Eighth grade.
  • K.C. tried to pass herself as her fictional cousin, Cassandra Bailey again.
  • The character of "Susie," had a few lines which were cut, which would have revealed she named her goldfish, "Goldie."  
  • Also cut, were lines of how hot Bruno Mars was despite the fact the girls towered over him, and that K.C. and Amy once took Spanish together.
  • This episode marked the first appearances of Amy Bishop and her fake parents Danielle Bishop and Mitch Bishop.


Agent Johnson All right, folks, this is a big one. We just got intel that enemy agents are hiding right here in the DC Metro area pretending to be ordinary citizens.

K.C. That is despicable... except for when we do it.

Ernie You know, we haven't spent this much time together since our trip to Niagara Falls.
K.C. Ha! Yeah, I remember that. You almost fell in.
Ernie I didn't almost fall in. You pushed me!
Kira You told us he slipped!

K.C. He did slip. After I pushed him.

Amy K.C., would you please tell me what's going on!
K.C. K.C.? Uh, I think you have me confused for somebody else. I'm not K.C., I'm, uh, I'm her cousin Cassandra.

Kira Really? We doing that again?


Season 1
PilotMy Sister from Another Mother... BoardGive Me A “K”! Give Me A “C”!Off the GridPhoto BombedHow K.C. Got Her Swag BackDaddy's Little PrincessAssignment: Get That Assignment!Spy-anoia Will Destroy YaDouble Crossed Part 1Double Crossed Part 2Double Crossed Part 3Stakeout TakeoutThe Neighborhood WatchdogsFirst FriendOperation: Other Side Part 1Operation: Other Side Part 2K.C. and the Vanishing LadyDebutante BallerK.C.'s the ManRunaway RobotAll Howls EveThe Get Along VaultEnemy of the State'Twas the Fight Before ChristmasK.C. and Brett: The Final Chapter - Part 1K.C. and Brett: The Final Chapter - Part 2
Season 2
Coopers Reactivated!Do You Want to Know a SecretRebel with a CuzThe Mother of All MissionsAccidents Will HappenBrainwashedThe Truth HurtsDown in the DumpsDance Like No One's WatchingThe Love JinxK.C. Levels UpCatch Him If You CanSup, Dawg?Tightrope of DoomThe Legend of Bad, Bad Cleo BrownSpy of the Year AwardsIn Too Deep, Part 1In Too Deep, Part 2Virtual InsanityUndercover MotherTrust No OneHolly Holly Not So JollyCollision CourseFamily Feud
Season 3
Coopers on the RunWelcome to the JungleOut of the Water and Into the FireWeb of LiesTeen DramaK.C. Under ConstructionThe Storm MakerKeep on Truckin'Unmasking the EnemyThe Truth Will Set You FreeStormy WeatherDeleted!Second ChancesRevenge of the Van PeopleThe Gammy FilesTake Me OutTwin It to Win ItCassandra UndercoverK.C. Times ThreeThe Domino EffectDomino 2: BarbecuedDomino 3: Buggin' OutDomino 4: The MaskK.C. Undercover: The Final Chapter