- "Hi! I'm Numbuh 1-2-3, and I used to have pale, flabby and useless thumbs until I came up with a program guaranteed to give you the thumbs you've always dreamed of, in just thirty days!"
– Numbuh 1-2-3 advertising his Thumbercise
Numbuh 1-2-3 is a Kids Next Door fitness instructor.
History
He was recruited into the Cadets Next Door and went to train at the Kids Next Door Arctic Base, before being initiated into the Kids Next Door and choosing his codename.
He attended the Kids Next Door 2x4 Technology Convention, where he showcased his new invention called the "Thumbercise". The advertisement he played during his presentation was starring Numbuh 13, where his life greatly improved by exercising his thumbs. However, Numbuh 74.239 pointed out it was actually nothing more than a rubber band. This prompted Numbuh 1-2-3 to run away using one of Sector C's Smoku Tarts when his own team of exercisers realized the same thing (Operation: S.C.I.E.N.C.E.).
Trivia
- He seems to be a parody of Richard Simmons.
- His codename is a reference to counting from one to three to hold a rhythm during aerobics.