Numbuh 363 (Harvey McKenzie) is the younger brother of Numbuh 362 and leader of Sector W. He is voiced by Jennifer Hale. He was introduced in Operation: Z.E.R.O., where he was seen taking a tour of the Kids Next Door Seriously Cool Museum of Artifacts and Stuff along with his teammates Numbuh 83 and Numbuh 84. Like his sister (and most other operatives but later on she believes Numbuh 0 exists when she found out that he was Numbuh 1's father), he does not believe that Numbuh 0 exists.