There are the book series we all know and love. You know the ones we're talking about.
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These are the series that dominate discussions IRL and on the Internet.
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Team Edward or Team Jacob, Team Gale or Team Peeta, you know the drill.
These series are so popular, they inspire new, derivative books.

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We're looking at you, Divergent and Fifty Shades of Grey.
Sometimes it's easy to forget that for every series with Harry Potter-levels of popularity, there are so many more.
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What about Margaret Peterson Haddix's Shadow Children books, which described a society where only two children are allowed per family?
Or beyond YA series, why not have endless Internet conversations around Marilynne Robinson's Gilead Trilogy?
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Which will be a 'quartet,' according to Robinson at a talk she gave earlier this week at Columbia University.
Tell us in the comments: which underrated book series could use more love ~and why~?
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