K.C. Undercover Wiki
K.C., you know that I'm in love with you.

Brett Willis is a recurring character on K.C. Undercover and a central character in Season 1. He was K.C. Cooper's former boyfriend and mission partner. He is the son of Zane Willis and used to work for the Other Side as a training officer. He is currently a defector, leaving the Other Side for good, showing that there is good in him. Presumably, he is hiding out in Canada.

He is portrayed by Ross Butler.


Brett Willis is the son of Zane Willis, who trained his son for his revenge on Craig Cooper and Kira Cooper from their past life, his former friend turned enemy and his former crush. Brett joined The Organization as their top spy, winning junior spy of the year during the events of K.C. Undercover Season 1.

Double Crossed

K.C. Cooper and Brett are assigned an undercover mission as the two gain a disliking to each other. Eventually, Marisa takes an interest in Brett, and the two soon going out, leading to K.C. to become jealous. During a dancing competition, the two take an interest with one another and began dating soon afterward. When Zane sends flowers and warning that he's coming for them, Brett tells the family that Zane is imprisoned and that he had sent the flowers and note from a computer at the prison. After gaining the family's trust, and K.C.'s affection, Brett calls his father to tell that the Cooper family has fallen for his false story.

Afterward, Brett succeeds in manipulating K.C. to going to a "Beyoncé concert" out of state, leading to K.C. being strapped to her seat and Brett revealing the truth. Taking her to Zane's hideout, she is tied and left in a barn. Though Brett is told that he is good by K.C., this is stopped by Zane, who enters and reveals he had an agent become K.C.'s look-alike.

But the plan fails with Marisa learning that the K.C. look-alike is fake, and going to the hideout and aiding K.C. into escaping. K.C. reaches to the Organization's HQ where Brett is waiting, he is defeated by K.C. and locked away.


After his father's arrest, Brett was kicked out of The Organization and joined the Other Side and became their top agent there as well, and trained new recruits.

The Other Side

Once K.C. has entered the Other Side, Brett and K.C. run into each other at training. The two through the episode bicker, but she frequently attempts to tell Brett there is good in him. This leads Brett in aiding K.C. during her battle with Victor and allowing her to escape, leaving him behind. This shows that he has good in him, eventually leading to him leaving the Other Side and needing the aid of K.C. during the last season.

K.C. and Brett: The Final Chapter

Brett is sent by the Other Side in order to eliminate K.C., but he couldn't bring himself to do it, but now needs K.C.'s help into bringing him back to The Organization, leading to the Cooper Family to worry if The Organization will learn that Brett is living at their residence. Also leads with the tension of the Cooper Family distrusting Brett, as K.C. attempts to aid him.


Brett is currently hiding out in Canada as he is a fugitive for both, The Other Side and The Organization.



Zane Willis

Brett's father, the arch nemesis of the Cooper family. Brett fulfils anything his father requests, even if it goes against what he really wants.

Love Interests

K.C. Cooper

Main article: K.C. and Brett

In Double Crossed Part 1, Brett and K.C. are ordered to work together, and act as a couple for a mission, though K.C. initially dislikes him. They become a real couple at the end of the episode after they admit their feelings for each other. However, they evidently break up in Double Crossed Part 2 after he kidnaps her. Despite Brett deceiving K.C., he admits his feelings for her were real.

In Operation: Other Side Part 2, Brett helps K.C. with her mission and her escape from the Other Side. In the same episode, K.C. persuades him to escape with her and return to the organization, but he stays behind, admitting he isn't one of those "good guys". In K.C. and Brett: The Final Chapter - Part 2 he and K.C. tell each other they love each other and they protect each other.

Marisa Miller

Brett and Marisa briefly date in Double Crossed Part 1, until Marisa breaks up with him (through K.C.) so that Brett and K.C. can start dating.

Ursula Timmcoy

Brett revealed in K.C. and Brett: The Final Chapter - Part 1, that Ursula was his girlfriend.

In K.C. and Brett: The Final Chapter - Part 2, Brett officially broke up with Ursula enraging her enough to try to eliminate Brett and K.C. (which was originally Ursula's assignment from Victor)


Season 1

Season 2

Season 3

Mentioned in:

Season 2


  • He was K.C.'s boyfriend.
  • He once called K.C. "babe".
  • In K.C. and Brett: The Final Chapter - Part 1, Brett's mission was to eliminate K.C. but he couldn't do it so K.C. had to protect him from The Other Side.
  • There is goodness in him as shown when he helped K.C. defeat Victor and The Other Side.
  • Brett made a move on Marisa.
  • He double-crossed the Cooper family.
  • He is Zane's son, but didn't tell anyone or it would blow his cover.
  • He is still in love with K.C.
  • Brett returns in the episode, Virtual Insanity, but he only appears as an illusion at the end of the episode.
  • Due to Ross Butler's role as Zach Dempsey in "13 Reasons Why", he did not appear in Season 3.


To view the Brett Willis gallery, click here.

Main Characters
K.C. CooperMarisa MillerKira CooperCraig CooperErnie CooperJudy Cooper