When books are adapted for television series or movies, there are different approaches to how this can be done.
According to the Guardian, "Boardwalk Empire", the HBO series set in the prohibition era, has already squeezed four seasons out of the 312-page book by which it was inspired. Hit series "Game of Thrones" on the other hand is much more economical with its source material. Its first three seasons, clocking in at 26.5 hours, cover 1,980 pages of George R.R. Martin's "A Song of Fire and Ice" epic. That means "Game of Thrones" gets 0.8 minutes of screen time out of a page while "Boardwalk Empire" spends 8.77 minutes per page of the book it's based on.
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