NEW YORK—Hermione Granger is keenly intelligent, unfailingly resourceful, ever logical, both a tad bossy and a tad insecure, and she believes in using her powers for good. Or maybe, in fact, that’s the actor, Emma Watson. Even she can’t really say for certain.

“I feel that so much of me went into her and so much of her went into me, I can’t really differentiate too much anymore,” Watson says, pondering the character she’s played in eight Harry Potter films, including the latest and (supposedly) last, Harry Potter and the Deathly Hallows: Part 2 (which opens Friday [July 15] ). “It’s all a bit of a blur.”

Playing a very famous character in a very famous film series for more than half of one’s 21 years, who wouldn’t get a wee bit confused about just where the actor ends and the character begins? Or vice versa. The character, of course, is novelist J. K. Rowling’s fictional creation, a girl wizard who wields a wand and casts spells like a champ. The actor, meanwhile, is sitting in a room in New York’s Waldorf Astoria hotel, answering questions about her counterpart and herself and about what, exactly, she will do now that she won’t be playing herself as Hermione anymore—or playing Hermione as herself.

She is wearing a Givenchy halter minidress involving tiers of black ostrich feathers, a confection that it’s tricky to imagine Hermione willingly stepping into. Her hair is a slightly longer version of the Mia Farrow–style pixie cut she suddenly appeared in—to much attention and some flak—last summer. What look like diamonds dangle from her ears. In person, Watson appears more delicate than she does on-screen, her British accent more precise, her manner almost painfully sincere and sweet. One is reminded that despite being an actor who earned $15,000,000 for each of the last two Potter films, she is still very young.

“The last shot we did was this kind of strange moment where we dive into the fireplace in the Ministry of Magic,” she says, when asked what was her big final moment of filming on the series she began as a rather bushy-haired nine-year-old so long ago. “Dan, Rupert, and I one by one jumped onto these blue safety mats, basically. And that was the shot. That was it. It seemed like kind of a strange one to go out on, but actually David [Yates, the director] made the point that we were, like, leaping into the unknown. It was kind of like a perfect metaphor for what we were all about to go into. It’s so funny. I can’t tell you how I felt when we were shooting it. I was just kind of numb.”

Before leaping into the unknown of real life, the trio of young actors—Watson, Daniel Radcliffe as Harry, and Rupert Grint, who plays Ron Weasley—was required to do something possibly trickier in Deathly Hallows parts one and two than jumping onto blue safety mats. As the films ramped up to a climactic battle between wizards good and bad, Watson found herself having to actually, well, emote. The “darker” films were an opportunity to “stretch”, she says, “and really feel like I was an actress and like I was acting, because actually for the first how many years, I didn’t really feel like I was doing much acting at all.”

Not long ago, questions of whether she could act and whether, after the series cast its final spell, she would act again still lurked in her mind, as dark and scary as the films’ evil Dementors. She took a deep breath, figuratively speaking. Then she took her first role ever (not counting a voice-over in The Tale of Despereaux) that wasn’t Hermione, in a small film called The Perks of Being a Wallflower. It was shooting in Pittsburgh. She was “terrified”.

“I was so nervous doing a different accent, being on a new movie set in a foreign country, with a crew that I didn’t know and a cast I didn’t know,” she says. One scene required her to mimic Susan Sarandon’s Janet in The Rocky Horror Picture Show. “I’m standing in a corset in front of all of these extras, trying to do this dance. And I felt ridiculous.”

But in the end, “I had the best six weeks. Having an experience like that outside of Harry Potter was what really convinced me that acting really was what I should be doing and that I was good at it. I’m excited about being an actress now in a way that I wasn’t so sure of when I was younger.” She thinks. “Sometimes you’ve just got to blast through and have faith.”

Watson will attend Oxford in the fall, continuing studies she began at Brown University. She’s nowhere near her 22nd birthday and yet she’s been famous for as long as she can remember, in places she once couldn’t imagine. “I was in a shantytown in Bangladesh,” she says, “and a boy stopped me in the street and said: ”˜You’re the girl from Harry Potter.’ I was like, ”˜Wow, I really can’t go anywhere. This is incredible.’ ”

And not a bad thing, really.

Watch the trailer for Harry Potter and the Deathly Hallows: Part 2.