Book to film adaptations are commonplace in Hollywood, but that doesn't mean transporting stories from pages to screen is an easy feat.
Or an automatic win.
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Some adaptations are very successful: Think Harry Potter, Lord of the Rings and The Hunger Games. Comic book adaptations such as those from the Marvel cinematic universe have become some of the biggest films in the world.
But others are not that good, or actually just bad. Here are eight of the very worst.
My Sister's Keeper.
Now don't get us wrong: Both the book and movie adaption of Jodi Picoult's My Sister's Keeper are utterly gut-wrenching. Like, physical pain-inducing level sad.