Harry Potter (household name Daniel Radcliffe) begins his sixth year (and sixth film) at Hogwarts School of Witchcraft and Wizardry with old friends Ron and Hermione (Rupert Grint, Emma Watson).

Early in the term, Harry happens upon an old and extraordinary book marked “Property of the Half-Blood Prince.” The book, the identity of the prince and his influence on Harry Potter’s life pretty much drive the tale forward.

At its best (and I believe “Harry Potter” 6 is one of the franchise’s better efforts), Potter and friends inhabit an enchanting, wonderfully crafted alter reality. To the film’s credit, it takes itself seriously enough to fully immerse us in this magic-savvy realm. The sets are meticulously created, and one drifts effortlessly into Potter’s universe of spells and potions.

At its worst, one is reminded—a bit too often perhaps—that “The Half-Blood Prince” is really a segue film, preparing us for “Potters” 7 and 8, the anticipated conclusion of the Harry Potter fantasy.

Yet even as a segue, “The Half-Blood Prince” is a cut above many franchises that race helterskelter from first film to last (the last “Terminator” suffered from this malady, as did “Star Wars’” later efforts). But lots happens in “Harry Potter” 6: Characters develop, friends fall—and, of course, the plot thickens.

Another plus: Radcliffe, Grint and Watson have returned intact for yet another “Potter” installment. It’s a remarkable achievement in this day and age of scheduling conflicts, salary negotiations and inflated egos for a franchise to survive with its founding cast.

A few years hence, when those Potter-philes among us— and you know who you are—sit down for that inevitable 18-hour, rainy Saturday Potter-thon, I do believe watching Radcliffe and company mature throughout the series will be worth not getting off the couch.

As the cast ages, both adult conflicts and adult relationships begin to emerge forebodingly. There’s actually a trace of sexual tension in “The Half-Blood Prince”; relationships develop with the same speed and dexterity as do Potter’s adversaries.

I have to say, however, that my wife mourns the passing of the younger, more carefree Potter clan. Once upon a time, Harry Potter evoked a magical land with a far less sinister, fairy-tale quality—but Hogwarts has since evolved (for better or worse) into an adult fantasy realm of good versus evil. People die (albeit with little bloodshed), and one surmises that the final two episodes will unfold with an even greater epochal intensity.

There’s really nothing cutting-edge about the latest Potter installment. Author J.K. Rowling has lined up her magical ducks in proper order—we’ve seen similar plot development throughout the history of the written word.

Instead of twists and turns, we get likable characters and a feature-rich milieu. Then again, “Potter” 6 is the franchise’s equivalent of a seventh-inning stretch—and one feels loose ends tightened and necessary developments deftly lured into play. The real magic, one surmises, begins with “Harry Potter and the Deathly Hallows (Part 1)” due out next year.

All in all, however (and I’ve never read Rowling’s books nor have I awaited a “Potter” installment with bated breath), I do believe that the series is probably one of cinema’s best franchises in terms of sheer storytelling power, cast enchantment and first-rate production values.

What “Star Wars” did for the last generation (that is, emerge as a warts-and-all cult masterpiece), I suspect “Harry Potter” will do for this generation. Good for Potter and good for us.