Terry Gilliam is the Howard Stern of filmdom. He’s irreverent and provocative, and you’re either going to love his work or hate it.

The director has delivered some of the most profoundly bold fantasies ever made: “Time Bandits” and “Brazil” in the ’80s, “The Fisher King” and “Twelve Monkeys” in the ’90s. For those who find feature films predictable and mundane—well, I suspect you’ve never seen a Terry Gilliam film.

“The Imaginarium of Doctor Parnassus” begins with such bold promise. Christopher Plummer plays the title role, an immortal being gambling with the devil for human souls. Why, you ask? Oh, don’t go there.

Parnassus has wagered his daughter (exotic waif Lily Cole), and the devil is waiting for the game to conclude. Parnassus and company are sideshow carnival thespians, antiquated street performers lost in a thoroughly modern world. They find themselves in the night-shrouded slums of London, desperate to gamble the souls of poor drunkards stumbling from one pub or another.

They come upon Tony, a sweettalking con man with a few tricks up his sleeve—tricks that Parnassus realizes he can use to perhaps beat the devil for his daughter.

Did I mention the particular playground where these contests unfold is Parnassus’ mind itself (a magic doorway swallows the unsuspecting, much like the portal in “Being John Malkovich”). It’s an amazing realm of cinematic wonder and, yes, even fantastical beauty . . . but fraught with danger.

I suspect this film will long be remembered for Heath Ledger’s final performance. Ledger plays Tony, of course, a lost yet seemingly earnest soul seeking redemption. Parnassus offers the perfect redemptive palace, if only Tony can wager correctly.

But Tony never gets to wager. Ledger never gives him the chance.

The film that Gilliam desperately tries to piece together after Ledger’s death splinters somewhere along the way, and one senses a disjointed semblance of unfulfilled promise. Johnny Depp, Jude Law and Colin Farrell attempt to step into Ledger’s shoes within Parnassus’ realm—Gilliam presents a credible possibility, but the substitution never gels.

A pity, of course. If Ledger had lived, one can only wonder what the film would have been. For Gilliam fans, for Ledger fans, the film may prove a curiosity, but even Gilliam’s fertile imagination can’t overcome the tragic loss of Heath Ledger. It is, at best, an incomplete tribute to a fine actor, a strangely surreal footnote in the history of cinema.

Interesting premise for bloodsucker fans. A virus has perpetrated a race of vampires; 10 years from now the undead have all but repopulated the earth, at the expense of a rapidly dwindling human race.

By the year 2019, most of humanity has either succumbed to becoming vampires (working the obligatory 9 to 5—and those would be p.m to a.m. hours) or been reduced to a gruesome captivity, pumping out blood to feed the nocturnal hoards of the undead.

The problem is there are so many vampires, so few remaining humans, that an imminent blood shortage threatens the entire existence of the night workers. Intrepid entrepreneurs are hurrying to develop a synthetic blood substitute.

“Daybreakers” begins with promise—even though this is a vampire flick from Australia, a country not squeamish about filming blood flow. In “Daybreakers,” directing brothers Peter and Michael Spierig have pumped a considerable chunk of their production budget into saturating the screen in a liquid crimson hue.

Ethan Hawke plays a medical scientist, a reluctant vampire (he shuns human blood) working to find a blood substitute. He’s empathetic to the few remaining humans and thus frowned upon by many of his brethren, but the clock is ticking—the shortage is rampant and hunger riots are breaking out.

So, yeah, the film’s first half simmers with a novel, ethereal edge. But then somebody reminds the Spierig bros that this is a vam pire movie, damn it! More ripped throats, more gushing blood! Just when a cure is at hand, the film spirals down into a generic bloodbath filled with a plethora of last-second reprieves for Hawke and his new human friends, fraught with double-crosses and carnage and fountains of unleashed arteries.

Willem Dafoe has a few nice moments as an ex-vamp with newfound humanity, but this film’s reduced to little more than a crimson orgy. Vampire lovers may be placated, but what might have been a thoughtful new approach ends as little more than the same ol’, same ol’ horror flick. Color me red.