11. Topher Grace As Venom (Spider-Man 3)
Casting Topher Grace as Venom in Spider-Man 3 remains one of the worst ideas in the long, sad history of bad ideas.
In all fairness to the actor, many of the criticisms launched at his symbiotic villain can be blamed on the script, but the point that he was all wrong for the part still stands.
Venom is supposed to be imposing, scary, a brooding psychopath - Grace wouldn't be frightening if he ran at you in a dark alley sporting a chainsaw and hockey mask.
Although the screenplay painted him as a sniveling weasel who gets everything he deserves, an alternative choice of actor would have brought a different dynamic to the role and captured more of the character's essence.
Tom Hardy has been cast as Eddie Brock in Sony Pictures' upcoming Venom spinoff, which sounds a lot more like it.