Time to put away childish things in the world of Harry Potter, as the former boy wizard, now firmly reaching manhood, begins his inexorable march to a death match with Lord Voldemort. The latest movie is titled Harry Potter and the Half-Blood Prince, but that's slightly misleading. This movie is about Albus Dumbledore, again played with Gandalfian royalty by Michael Gambon, as he leads Harry (Daniel Radcliffe) through a gantlet of spells, potions and revelations to the end that J.K. Rowling's readers already know. I'm not among that horde, so reaching this sixth Potter movie and still being interested even more so after this one's downbeat finale says something about how this franchise continues to mature. I'm still not sure whether the finale needs to be divided into two more movies as planned for Harry Potter and the Deathly Hallows, but Dumbledore's sagacity and sacrifice here earn the benefit of any doubts. Director David Yates returns for his second Potter flick, continuing the darker vibe he brought to The Order of the Phoenix. That's obvious from our first look at Harry, bloodied and shaken by his latest encounter with Voldemort. But he's growing into his predestined role as savior, with Dumbledore providing key clues for how to do it. Yet at the finale, after a moving farewell to a major character, Harry's declaration that everything happening beforehand meant nothing has an unsettling ring of truth. It's a problem that the series has faced since its inception; Rowling stumbled into a gold mine with the first book, then needed to weave occasionally irrelevant twists and crises to stretch the paydays. Bringing Dumbledore to the fore is a wise move, since he seems to know exactly how everything turns out but won't reveal it to anyone, especially Harry. He whisks his star pupil to a meeting with Hogwarts' latest addition, the potions professor Horace Slughorn (Jim Broadbent, a wonderful choice). Puzzled by what the elders hide, Harry often fades into the background. Slughorn's addled expertise and a few of Dumbledore's bottled memories of the student Tom Riddle, who'll become Voldemort, add new dimensions to the series. The same goes for Draco Malfoy (Tom Felton), who's growing beyond being merely a school bully into a strangely conflicted agent of dark forces. Voldemort reverts to his storm-cloud apparition of earlier films, with Ralph Fiennes glimpsed only for a nanosecond. The Dumbledore/Slughorn scenes are so effective that when screenwriter Steve Kloves turns back to the students' frivolous sides more puppy love crushes, another Quidditch match, etc. it feels unnecessary. Harry Potter and the Half-Blood Prince contains more humor than usual, which is jarring considering the heavy drama in between. Nice to see the students enjoying pub time and snogging now and then, but it's obviously catering to young ticket buyers. Even the special effects have a more grownup feel. No elaborate creatures this time, but the black smoke comet Death Eaters and a climactic rush of unexplained undeads lend a sophisticated feel. Two scenes added for the movie the Death Eaters destroying a London bridge and attacking a supposedly safe house are added purely for action's sake. Yates isn't out to wow audiences but to emotionally involve them. It mostly works, from a nonreader's perspective, making this one of the franchise's high points. There won't be any problem at all for Rowling's devotees. Steve Persall can be reached at persallsptimes.com or (727) 893-8365. Read his blog, Reeling in the Years, at blogs.tampabay.com/movies. . Review Harry Potter and the Half-Blood Prince Grade: A- Director: David Yates Cast: Daniel Radcliffe, Michael Gambon, Jim Broadbent, Emma Watson, Rupert Grint, Helena Bonham Carter, Alan Rickman, Tom Felton, Maggie Smith, Bonnie Wright, David Thewlis Screenplay: Steve Kloves, based on the novel by J.K. Rowling Rating: PG; scary images, fantasy violence, mild profanity and sensuality Running time: 153 min. 