Numbuh 5

Abby Lincoln a.k.a. Numbuh 5 is the intelligent, relaxed girl second-in-command/spy in Sector V. She became a KND operative three years before the show started as shown in Operation: M.A.U.R.I.C.E.. She was trained by her older sister, Cree (Numbuh 11), and joined her sister, Numbuhs 8a and 8b, and Numbuh 9 in Sector V.