Ahead of the NBC comedy’s sophomore season, four Eastland Academy students were “expelled,” so to speak, and one newbie enrolled: Nancy McKeon’s hard-edged biker chick Jo Polniaczek, the antithesis of — and perfect foil for — snooty, superficial Blair Warner.

Turned out that push/pull was just what the show needed; Season 2 saw it moved from ratings probation to the network’s honor roll.

https://tvline.com/lists/best-tv-characters-late-cast-additions-seinfeld-buffy-the-office/best-tv-characters-late-cast-additions-luka-abby-er/