Now adults and started their own families, Numbuhs 2 through 5 continued to be Kids Next Door operatives as secret undercover adults. However, a new villain has somehow discovered and are hunting down the Teen & Adult operatives, including the original Sector V. So Numbuhs 2-5 must seek the aid of their own children and few members of the Kids Next Door that know their secret, before Kids Next Door of all ages are destroyed.
