The word “universe” is standard parlance in the comic book industry. The term is used to remind us that despite superheroes’ singular abilities, they are not alone in their fictional world — they cross paths, they form alliances, they fight. This is true of the Marvel Universe, which includes Spider-Man, Iron Man, and the X-Men, and the DC Universe, home to Superman, Batman, and Green Lantern. If there’s one thing that comics readers have always dug, it’s a team-up.

You don’t hear “universe” much in the film industry. Here in the real world — or Hollywood, at any rate — the prospect of mingling franchise characters is dauntingly complicated. Sure, we get a novelty such as “Alien vs. Predator” here and there, but rarely. Different studios hold rights to characters. Actors’ contracts can be tricky to coordinate — and so can their egos, one imagines. A standard-length script can start to feel crowded with multiple headliners in the mix. All of which makes the superhero crossover vehicle “Marvel’s The Avengers” the unlikeliest event movie of the summer. Who’d have thought — the Marvel Universe, in all its colorful sprawl, making the jump from the comics page to multiplex screens?