There are 2 books in the Batman: The Dark Knight Returns series. The newest book is Batman which came out in 2016.

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Batman Noir The Dark Knight Returns

Book cover of Batman Noir The Dark Knight Returns
It is ten years after an aging Batman has retired and Gotham City has sunk into decadence and lawlessness. Now as his city needs him most, the Dark Knight returns in a blaze of glory. Joined by Carrie Kelly, a teenage female Robin, Batman takes to the streets to end…
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It's the thirtieth anniversary of THE DARK KNIGHT RETURNS, and now DC Comics presents this classic title in a newly redesigned edition! Ten years after an aging Batman retired, Gotham City has sunk deeper into decadence and lawlessness. Now, when his city needs him most, the Dark Knight returns in…