"Don't touch me - don't ever touch me!"-- Numbuh 363
Numbuh 363 is selfish, greedy, unkind, and arrogant, to the point that pretty much everyone in the KND—except perhaps his sister—hates him. Numbuh 362's position as the Supreme Leader is most likely the only reason he remained in the KND. The adult Numbuh 4 says that he calculated Numbuh 363 to be "200 percent bananas," reminding him of a similar person he had met during his second year at Harvard University.
He debuted in Operation: Z.E.R.O., on 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), he did not believe that Numbuh 0 existed before the events of the movie.
Numbuh 363 returned in the series finale with a much bigger role. At the beginning of the episode, Numbuh 362 reassigns Sector W the mission of stealing the DCFDTL's birthday cake after Sector V fails one too many times, which Numbuh 363 rubs in Numbuh 1's face. When Numbuh 74.239 announces the massive scavenger hunt with the cake as the prize, Sector W goes after the most valuable of all the items on the list: Father's pipe. When they try to take the pipe, Sector V arrives to stop them, as taking it would anger Father immensely and surely get the three of them killed. Numbuh 1 grabs 363 and lectures him about teamwork, only for 363 to scream at Numbuh 1 for touching him.
This wakes Father, who tries to kill Numbuh 363 for taking his pipe as he continues to brag about it. Numbuh 1 intervenes to save him, but 363 continues to go after the pipe. When he grabs it, Father transforms into a dragon and blows a giant hole in the floor (that goes through the whole planet), injuring 363 in the process. After Sector V narrowly manages to knock Father out of battle by pushing him into the hole, Numbuh 363's remains concerned only about winning the scavenger hunt. This angers Sonia and Lee to the point where they gag him and give all the items they have collected, including the pipe, to Numbuh 1.
After this scene, the adult Numbuh 5 explains that some months later, when she took over the position of Supreme Leader, the first thing she did was have Numbuh 363 decommissioned.
Harvey was also seen in the background of the Treehouse level in the game, Cartoon Network Punch Time Explosion.
- While he clearly demonstrates many negative aspects unfitting for a leader, his team is stated to have the highest mission success rate in the entire KND organization, implying that he is a competent leader on some level. However, it is also possible that he forces them to do well on missions, that they have done fewer missions than other sectors, or that they are able to do well on missions without his leadership. Harvey does seem to take his missions seriously, most of it due to his competitiveness.
- His clothing colors are somewhat of an inversion of his sister's.
- He is revealed to have a bad case of Haphephobia. It is also possible he is OCD about people touching him.
- Due to his personality, many fans consider Numbuh 363 the worst character in the show.