Soylent Green was another, more respected, sci-fi film that also benefited greatly by Heston's presence. In this crime thriller Heston, set in a bleak future, utters one of the most famous lines in all of sci-fi filmdom. And since it's also one of the biggest spoilers in all of filmdom, we won't play that clip here, out of respect for the line. Soylent Green was also significant, film-historically, as the last film appearance by Edward G. Robinson, himself a legend.

In this scene, in a bit of well-crafted cinematic suspense spinning, Robinson imparts, out of earshot, the secret of the green soylent to Heston, which propels him through the rest of the film. It's an affecting scene, memorable for its imagery (both visual and aural) and for its emotion. Robinson was sick with the real-life affliction that would kill him. Pop culture-wise the poignancy of that moment will not be matched again until decades later, when Warren Zevon says good-bye to us on Letterman.

Lastly, there's also the potentially laughable-but-for-Heston, Planet of the Apes.

This was the earliest of his sci-fi trilogy and with the funny ape makeup could easily have been a disaster if anyone but Heston played Taylor, the stranded astronaut. Pity poor Roddy McDowell and Kim Hunter for having to undergo hours of make-up application as apes, but fer-cryin'-out-loud their mouths barely move. No matter, the gripping story, partly penned by master Rod Serling, and Heston came to the rescue.

In this clip, Heston himself discusses the inside-baseball of Planet of the Apes and how it came to be, with Greg Kinnear:

We've seen commentary in the past that treated Heston's sci-fi work as perhaps desperate career-salvaging hackery, a time-serving bridge until Hollywood could get to its attempt to revive itself via disaster films like Earthquake (in Sensaround!) and monster-budget war stories like Midway, where a whole lot of acting was not required.

It was anything but. Charlton Heston worked hard at his art, bringing stories to the screen and bringing his unique persona to them. Of this, the interview above hints, he was aware. And if you look at his IMDb entry, you'll see he worked right up to a few years ago.