Numbuh 274, Numbuh 11 and Numbuh 9. He was also an older brother to Bruce, Ashley and David of Cadmus was once an operative named Numbuh 421B/Joshua Wigglestein Uno, and the son of Father. He revolutionized the Kids Next Door, the rise of 2x4 Technology, the creation of the KND Arctic Prison and lots more. He trained operatives like Sector Z.
He discovered the virus of Adulthood as mentioned in Operation: I.N.T.E.R.V.I.E.W.S. and planned to wipe it out himself. This caused him to leave the KND and have his dad, Father to transform his siblings and their friends from Sector Z into the DCFDTL. Numbuh 421B on the other hand chased a Teen Ninja to the Costa Rica Volcano and during his fight with the Teen Ninja, fell into a molten pool and jumped out as quick as he can. The results left him burned and having most of his limbs removed. Father had planned for this to happen so Numbuh 421B was taken back to the Delightful Mansion and put into a machine suit (it parodies General Grievous and Darth Vader from Star Wars,) and become his second apprentice, Cadmus.
He does live in The Delightful Mansion, but underground in a bedroom and throne room on an island, surrounded by Hot Nacho Cheese.
Cadmus does secretly plan to overthrow Father after he destroys the KND with him and his siblings. He also has Chad Dickson as his secret apprentice. He has plotted various schemes behind Father's back, the teenager's plot in Operation: S.I.T.T.E.R., the combining of Gallagher and the Middle School in E.L.E.C.T.I.O.N.S. and the treaty trap in Operation: T.R.E.A.T.Y. He has a great lust for Cree Lincoln, Father's apprentice, and strongly hates The Steve. Like The Toiletnator, his greatest enemy is Numbuh 4 as shown in their character in Operation: C.A.D.M.U.S.. In Operation: D.O.O.M.S.D.A.Y., he teams up with Mother and her Inquisitive Children of the Mists using Chad Dickson, his brother, Jacob and their little sister, Numbuh 12 as their puppets. And is the mastermind behind the whole Stop the G:KND video and had slit Numbuh Infinity's throat the night Numbuh 1 joined G:KND.