Chris Evans as Captain America comes to mind. He had played an annoying Human Torch in a terrible Fantastic Four movie prior. No one thought he would become the character so much that it was impossible to re-cast it.
"Rob Lowe in Parks and Recreation. Based on some of his other work it didn’t seem like the role of an enthusiastic health nut fit him but he killed it."
Chris Evans as Captain America comes to mind. He had played an annoying Human Torch in a terrible Fantastic Four movie prior. No one thought he would become the character so much that it was impossible to re-cast it.