Harry Potter's back. What do you know?

Accio popcorn!

Potter fans, rejoice. After changing opening day more often than a Metamorphagus' hair color, "Harry Potter and the Half-Blood Prince" -- the series' first movie since author J.K. Rowling wrapped up the books in July 2007 -- finally opens Wednesday.

Based on the sixth book in Rowling's epic series, "Harry Potter and the Half-Blood Prince" features a more mature Harry dealing with the deaths of loved ones, the state of his love life and a prophecy that states that he must either kill or be killed in a duel with the world's most powerful dark wizard, Lord Voldemort. Pretty heavy stuff for a 16-year-old kid.

For those who might need a refresher course, we've put together a quick summary of what's what and who's who, plus some idea of what to expect in the new movie. A note: If you're new to the series, beware of spoilers.

The potions master

Hogwarts headmaster Albus Dumbledore won't hear a word against Severus Snape, but that doesn't change the fact that the bat-like professor is looking mighty suspicious in this flick. Well, Harry certainly thinks so. Antagonists from the start, Harry doesn't believe that Snape, who hated Harry's father, has truly reformed his Death Eater ways. Prof. Snape may have a new job in this installment, but he seems up to old tricks, such as torturing Harry in the classroom, meeting in secret with Harry's nemesis, Draco Malfoy, and generally bringing down the mood of any room he's in.

Keeping up with the Malfoys

Lessons with Dumbledore

Restored to his position as Hogwarts headmaster and fresh off his victory over Lord Voldemort, Dumbledore ought to be feeling pretty good. Although he remains the world's strongest wizard, there are those who worry that he's beginning to show his age. Dumbledore kept his distance from Harry in the last movie to protect them both while Voldemort manipulated Harry's thoughts, but he trusts Harry a bit more this time. The headmaster even takes Harry on a recruiting trip, gives him private lessons and sends him on an important quest in this film -- while keeping some choice secrets to himself.

In Fudge we trust?

In the last movie, it seemed the Ministry would stop at nothing to prevent Harry from telling the world that Voldemort had returned. Ministry employees such as Minister of Magic Cornelius Fudge and the prim and evil Prof. Dolores Umbridge set out to discredit and destroy Harry at every turn while maintaining that the Dark Lord was dead and gone. But as the ministry building itself was the setting of Dumbledore and Voldemort's epic battle at the end of "Order of the Phoenix," government officials are racing to backpedal from their former position.

All you need is love

You-Know-Who

He's bad. He's back. He's coming for you. Voldy may have lost the battle in the Ministry, but the arch-baddie of the magical world is gathering strength and has started to launch attacks on the Muggle world, as well. This movie reveals more about He-Who-Must-Not-Be-Named's lonely past as Harry and Dumbledore navigate through memories that document Lord Voldemort's mysterious family tree, his rise to prominence and his quenchless thirst for power and immortality.