The former "Lizzie McGuire" turns 18 soon and admits to MTV.com she knows she will have to ease into roles that are not so squeaky clean.
"This is a business and you have to give people what they want to see," she said. "It's the smartest thing."
But she said she has been holding onto a script for the past year that she'd love to star in. But that one, she said, is at least another year off.
The character is "so cool and weird and messed up. It's not like she's a druggie, she's just different, she's just in her head, she's crazy," Duff said. "I think it would be good for girls to see that."