Jack and Jill is Adam Sandler's undisputed masterpiece, and clearly a true classic of modern cinema.
In Sandler's previous film Funny People, he touched on the issue of comedic film stars doing ridiculous, awful children's movies. Posters such as "Re-Do" of a baby with a man's head, and "Mer-Man" littered the film, showing the career of a comedian who just needed some quick cash or even quick fame, willing to lower his standards to doing gimmicky kids films. Jack and Jill is his follow up piece of art, satirising and closely examining the genre that was the butt of a few, quick jokes in Funny People. When Sandler plays twin brother and sister, he is mirroring the performances of actual movie stars playing down their skills for quick cash, and even fame.
But he knew many people would only see his Jack and Jill performance as another quick cash grab, so he casted a well respected actor, Al Pacino, to star alongside him. He portrays the real actor that Sandler couldn't, being pulled down to the lowest of standards. Pacino even goes even further with the role, his characters mental breakdown mirroring the career breakdown that many would see Jack and Jill as. The cameos of famous actors, like Johnny Depp, also reflect this.
The bright colours, unfunny and childish jokes, and anything-but-subtle product placement are all things you would see in a run-of-the-mill crap kids movie, and Sandler takes all these elements to forge his shockingly realistic film satire.
Still, Sandler can't help but provide a few clues about the films underlying meaning through the movie. The scene in which Jack and Jill go to the cinema and act the same way, is in fact a mirror to society. It shows how all moviegoers watching these movies are braindead zombies, all acting the same way, all laughing at the same dumb jokes just because the people next them are. It's a deeply moving sequence.
Another clue is the scene where Jack and Jill partake in a double dutch skipping room competition. Although they both have not skipped in a long time, they instantly remember the same movements once they start. This is much like how film-makers of these movies get stuck in the same movements, and even when they try to move away and forget the awful kids films they made, they can't help but go back through the same motions.
One last clue as to where Jack and Jill's true intentions lie is when Jill goes on The Price Is Right. She spins the wheel, knocks herself out, and the scene ends with the host, Drew Carey, saying "Hey, lets give her a bunch of prizes!" This reflects the filmmakers again, and after making movies which truly suck, they are rewarded with big box office numbers and lots of money. They essentially are embarrassing themselves in the public eye, and are being "given a bunch of prizes" for it.
What's more, Sandler completely immerses himself in the roles of both Jack and Jill, crafting a realistic yet entertaining pair of twins. He obviously did immense research for the role, as shown by the REAL interviews at the beginning. This is probably his best performance ever.
Jack and Jill changed my views of cinema and society overall, and I cannot believe it hasn't gotten the critical acclaim it deserves. It saddens me to only see terrible reviews of it, and people can't see past it cleverly disguised exterior to it's insightful core. This is genius filmmaking, and I hope in years to come it is regarded as so.