Watch: LeVar Burton Explains the Incredible Impact of 'Roots' in an Exclusive Clip From 'Pioneers of Television'

How big a deal was the miniseries "Roots" when it was first broadcast on ABC in 1977? "They closed the casinos in Vegas when 'Roots' aired," explains cast member John Amos. "Nobody was on the streets." In this exclusive clip from the final episode of this season of PBS' "Pioneers of Television," Amos, LeVar Burton, Leslie Uggams and others talk about the incredible impact and reach that "Roots" had, as part of the upcoming "Miniseries" episode.

Narrated by Ryan Seacrest, "Pioneers of Television" explores the people and the shows that have shaped the medium of TV into what it is today. The "Miniseries" episodes, which airs on PBS on Tuesday, February 5th at 8pm, will be the fourth and final episode of a third season that's also explored comediennes, primetime soaps and superheroes.