Superman (1978), starring Christopher Reeve.

It involves Superman traveling at faster than c to save the day, rather than breaking a promise made under duress, which makes flunking ethical calculus into a super-vulnerability.

Movies based on comic book characters have come a long way. And even movies based on DC characters have advanced slightly.

Maybe, but the music from that movie is still iconic; more so than most other DC movies', except perhaps Elfman's Batman theme.

There are probably many from 1950 - 1980 to choose from. I've read many science fiction books from that era where the premise was such a bomb (though the destination was different). I'm not a movie buff, but I'd guess there is a superhero blockbuster with that theme somewhere in there ( Superman?).

This is from the first Christopher Reeve Superman movie.