By now, you may have already seen Guillermo del Toro's epic, guest-directed opening for the next Halloween-themed episode of 'The Simpsons.' But have you really seen it? The three-minute opening is as dense with jokes, sight gags and movie references as anything we've ever seen, so multiple viewings isn't an option -- it's a necessity.

Some of the characters and visuals del Toro pulls out are obvious. Some are references to films that only a tiny fraction of the 'Simpsons' audience would have heard of. However, they all feel like they come from the heart of a true horror geek and genre aficionado. del Toro getting three minutes to cram as many things that he loves into the world of 'The Simpsons' is one of the coolest and craziest things to happen to the show in a decade.

We went through the footage and pulled out some of the best, craziest and deepest references. But we know the truth: we're still missing a bunch of 'em. Check out what we found and help us fill in the gaps in the comments below!