"This is a film that will definitely frighten people and get people jumping out of their seats," Radcliffe said.
The young man who played "Harry Potter" for ten years feels that while those films did have scary moments, the chills in this one are on an entirely different level.
"All the scary stuff in 'Potter' came from some quite big or heightened moments, whereas a lot of this film can feel quite real," he said. "So the psychological element is such so that if you have young kids, or kids under 12, I would really not take them because you will have a lot sleepless nights after seeing this movie."
The 22-year-old actor said this film should help him transition away from all things "Potter" and into more adult roles. He started down that road several years ago with his work on the stage.
"The value of doing 'Equus,' the play in both London and New York, is that it made people sit up and go, 'Oh, he wants to do something different, he's serious about this, he doesn't want to rest on his laurels and he's willing to take risks,'" Radcliffe said.
Radcliffe has a couple fellow "Potter" alums he sees as risk-taking role models.
"I look at actors' careers like Gary Oldman, or Alan Rickman, and people I've worked with, and there's such diversity in their work, it's very inspirational," the actor said.
That admiration carries over this Oscar season, as Radcliffe roots for his nominated friend, Gary Oldman.
"That's what I really wanna see happen is Gary up there getting an Oscar. That would be amazing," he said.
"The Woman in Black" is rated PG-13 and is in theaters now.