Harry Potter's entire life leading up to "Harry Potter and the Half-Blood Prince" has been plagued by dark magic and loss. His sixth year at Hogwarts School of Witchcraft and Wizardry marks a turning point as he begins to fall in love with Ginny Weasley. Numerous obstacles, including his own destiny, stand in the way: Lord Voldemort ignites the Second Wizarding War, and Harry's status as the "Chosen One" becomes more evident.

The title character in J.K. Rowling's epic series famously earned his reputation at just over a year old, when Voldemort murdered his parents but failed to finish Harry off with a Killing Curse. Though Harry's heroic mother and father were kept secret from him until he received his invitation to attend Hogwarts at age 11, his peers' high expectations and the deadly threats from Voldemort have remained consistent reminders that a great responsibility rests on his shoulders.

Daniel Radcliffe had a brief but noteworthy acting résumé when he accepted the life-altering role of Harry Potter. He had already appeared in a BBC production of "David Copperfield" with his future "Harry Potter and the Sorcerer's Stone" co-star Maggie Smith, as well as "The Tailor of Panama" with Pierce Brosnan and Jamie Lee Curtis. His age synced up with the part in a way few actors get to experience, and he's grown up along with Harry through each sequel.

Harry's relationships and duties as one of the most powerful wizards in existence have only become more complex as he's aged. Director Chris Columbus' playful scenes with the first-year students of Hogwarts in "The Sorcerer's Stone" have since given way to David Yates' apocalyptic visions, which surround Harry during Dumbledore's warnings and the Death Eater invasion in "The Half-Blood Prince." Even as the final war sets in, Harry's life gets more complicated as he falls in love with his best friend's younger sister, who watched him depart for the first time on the Hogwarts Express years earlier.

At 19, Radcliffe now has an enviably prominent and diverse body of work on which to build the rest of his acting career. In 2007, he departed from the boyish innocence and ample clothing of the Potter films when he took on the lead role in "Equus," a play about a young man obsessed with horses. He's also starred in the Australian film "December Boys" and may take on an extremely serious role for his first post-Potter project, "The Journey Is the Destination," the story of a young photographer killed in Somalia. He still has quite some time before his days as Harry end, however, since "Harry Potter and the Deathly Hallows: Part II" doesn't come to theaters until July 2011.

Check out everything we've got on "Harry Potter and the Half-Blood Prince."

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