We bet you've never noticed these superhero movie Easter eggs

Superhero movies are so stuffed full of clever references to mythology and knowing nods to the past, it's hard to catch them all. However hardcore a fan you are, some will inevitably slip through the net.

Like, did you know in 1978's Superman: The Movie, a young Clark Kent runs past a train that happens to have a young Lois Lane in it? Lois is sat with her parents, who aren't just any old extras. They are played by actors Kirk Alyn and Noel Neill, who were Clark Kent and Lois Lane in the 1940s Superman serials. Inspired, eh?