I suppose that's why licensed settings retain a measure of popularity. It's much easier for players to jump into the worlds of Doctor Who or Star Wars or Lord of the Rings or DC Comics, but unless you have a group of homogeneously geeky players who are all equal fans of the same property, you're still going to hit a snag with immersion. And often, players will admit to some insecurity if they're not as knowledgeable as you are about a chosen setting.
I think most gaming groups fudge the details and create a version of the setting that THEY recognize, especially over time as their characters discover and shape it. That's not what this article is about. This article is about jump-starting a game or campaign from a shared experience. The whole group can't be expected to read a sourcebook together. It's also unlikely to experience an entire franchise as a group. So let's chop it down to a bare minimum. A single movie.
Here's the experiment: Watch a single film as a group, then decide very quickly what would happen next. The players could take the roles of characters from the film itself, or create their own who pick up where those tragic heroes left off. It'll possibly be a "side-story" that occurs in parallel. You might even want to set it before the film and make a prequel of it. Regardless, the idea would be to turn the film into an easily digested video sourcebook everyone has had access to simultaneously. The game system is academic, whatever you prefer really, usually something generic that can cover anything. GURPS, FATE, Savage Worlds, d20, whatever. The GM CAN do that research before hand and chosen something that fits the tone of the selected film. Is the action cinematic? Gritty? Does it feature super-powers, magic, martial arts? Etc.
It's your chance to make sequels to the films you loved but general audiences didn't, or at least, not enough. Maybe you could even rewrite history and take the reigns of a franchise before you stopped liking it. I mean, where would YOU take The Matrix franchise if Reloaded never happened? Another twist on this idea is to watch a TV pilot for a show that either didn't go to series, or that no one in the group ever watched, and just build from there. This is a case where players not having a firm grasp on pop culture actually HELPS.
So there you go, some inspiration to kickstart one-offs and mini-campaigns, surely. What movie would YOU tackle?