You didn’t have to watch more than the opening sequence of 2009’s “Inglourious Basterds” to know Christoph Waltz had the Best Supporting Actor Oscar all but wrapped up.

The actor’s post-Oscar career remains a head scratcher. Yes, it’s too soon to label his career a letdown, but often the best scripts actors ever see come after they’ve grabbed that gleaming statuette.

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Waltz’s first gig after “Basterds” came via “The Green Hornet,” an awkward superhero comedy from director Michel Gondry. Waltz played the film’s arch villain, an unremarkable baddie with an inferiority complex. Mediocre movie, less than flattering role for someone of Waltz’s abilities.

But “The Green Hornet” was practically “Citizen Kane” compared to “The Three Musketeers,” the recent mega-bomb casting Waltz as the evil Cardinal with designs on the kingdom. It’s the kind of work an actor grabs when there’s little else around, or they’ve got a serious case of swashbuckle envy.

What possessed Waltz to team up with B-movie director Paul W.S. Anderson (“Death Race,” “Alien vs. Predator”) and a gaggle of foppish actors attempting to revive a dormant franchise?

Waltz’s best post-Oscar future remains “Water for Elephants,” an engaging circus drama which cast the actor as the complicated third wheel in a tortured love triangle. The film, just released on Blu-ray and DVD, also marks co-star Robert Pattinson’s best work outside the “Twilight” franchise. Or inside, to be precise.

Waltz brings a dash of ambivalence to an otherwise mustache-twirling role, precisely the elements that helped make his turn in “Basterds” so memorable. “Elephant’s” lethargic love story, alas, devalued his performance.

This fall, Waltz looks to re-set his career with “Carnage,” a dark comedy co-starring Kate Winslet, Jodie Foster and John C. Reilly. It’s got that heady whiff of Oscar potential, especially since Roman Polanski is behind the camera.

If that fails, Waltz could simple wait until his new project with “Basterds” director Quentin Tarantino hits theaters. The actor will reteam with Tarantino for the upcoming western “Django Unchained.”

But by then, the glow of his Oscar victor could have long since faded.