A spin-off of a July 2001 special in which the infant and toddler characters of the classic cartoon series Rugrats were given a chance to peer ten years into their future, All Grown Up further developed the premise by depicting the title characters as "tween-agers." Though bigger and more loquacious, they were the same old Rugrats: imperious Angelica continued to lord it over her friends and follow trends, Tommy Pickles was still a natural-born leader, Chuckie was a worry wart, and twins Lil and Phil struggled to establish their own separate identities. New wrinkles to the old format included the burgeoning singing career of the kids' African-American friend Susie, the precocious interference of Tommy's brother Dil and Chuckie's adopted sister Kimi, and the antics of a new character, the kids' nerdish classmate Harold. First offered as a "sneak preview" by the Nickelodeon cable service on April 12, 2003, All Grown Up graduated to weekly status the following fall.
by Hal Erickson synopsis