Eric Stoltz as Marty McFly: See the 'Back to the Future' that almost was

It's long been known that Eric Stoltz was originally cast as Marty McFly in "Back to the Future." What we haven't seen -- until now -- was actual footage from Stoltz's brief time on the film.

Now, though, a few snippets of Stoltz as Marty -- including the famous scene where he sits down next to his future father (Crispin Glover) in a diner -- have been made public for the first time (you can see them in the clip above). They're part of the "Back to the Future" 25th anniversary Blu-ray set.

Stoltz shot five weeks' worth of scenes as McFly, but as director Robert Zemeckis, writer-producer Bob Gale and executive producer Steven Spielberg explain in the clip, his comic sensibilities didn't quite mesh with what they were looking for. He was replaced by Michael J. Fox, and you know the rest. Speaking of Fox, he recently filmed his own homage to "Back to the Future" for the 2010 Scream Awards.

Stoltz has done just fine as an actor -- his breakout film "Mask" was released a few months before "Back to the Future" in 1985, and he's been working steadily ever since, including his current role on "Caprica." And he has a place among the all-time might-have-beens in Hollywood, joining Tom Selleck as Indiana Jones and Sylvester Stallone as Axel Foley in "Beverly Hills Cop" (no, really).

We know there's no sound in any of the clips of Stoltz, and we also know the footage may not be color-corrected. But is it just us, or do the brief shots of Stoltz make that version of "Back to the Future" fell more like a wistful coming-of-age drama than a fast-paced comedy?

Follow Zap2it and Zap2itRick on Twitter and Zap2it on Facebook for the latest celeb news and buzz.