Felicity

Felicity, created by J.J. Abrams, was a television series on The WB starring Keri Russell as a sweet, introspective college student who should've picked Noel, dammit.
The series was nearly cancelled in its second season, after Russell cut her hair short. The resulting riots in 10 cities left 25 people dead, injured 124 more, and caused nearly $20 million in property damage. Russell went into hiding; her role was quickly recast with a long-haired lookalike, and Russell underwent extensive plastic surgery and adopted the name "Jennifer Garner" before resuming her acting career. Abrams gave her a supporting role on Felicity to ensure that the American public could not see through her disguise. Then, inspired by her experience in changing her appearance and going undercover, he created the ABC hit ﻿Alias expressly for her.
Greg Grunberg was brilliant though underused on this series, as in everything Abrams does.