This is, by far, the best film Adam Sandler has ever done. He plays basically the same character he always does (shy, socially awkward-type with an anger streak), but adds enough depth and small quirks to the character to make him likeable, if not loveable.
The film is a character study of a man named Barry Egan (Adam Sandler), a wholesale toilet plunger salesman with who is just a bit antisocial (possibly due to the constant torment he recieves from his seven sisters). But when one of those sister introduces him to a beautiful named Lena Leonard (Emily Watson), he'll see himself find love and- fuck it, I don't want to spoil it for you.
Now, there's something you must know before going into this film: this is not a typical Sandler film. You're not going to see any Happy Gilmores or Billy Madisons here. Just a strange, depressed, antisocial man that is given more depth and likeability than any character Sandler has played. Don't get me wrong, this is still a comedy, albeit a much more mature/dark comedy that most Adam Sandler fans are used to. This is a good thing, for it shows that Adam Sandler is able to diversify himself, and even give an oscar-worthy performance.
That being said, Sandler is truly stunning in his role as Barry Egan. He plays the role with enough subtlety to make the character very relateable. I mean, I'm sure anyone that's ever had multiple siblings can understand why this man threw a hammer through his sliding glass door as a child when his sisters kept calling him "gay boy". And I'm anyone who's ever had their loved one hurt because of their own stupid mistake can understand his violent rampage against a gang of blonde-haired brothers. Overall, his performance is highly enjoyable, and by far the best that Sandler has ever given.
Emily Watson is also wonderful as Lena Leonard. She's able to inject her character with both an air of mystery and a charming innocence. You really believe that she cares for and loves Barry, no matter how strange or eccentric or anti-social he may be.
Finally, let's look at Paul Thomas Anderson' directing, which is arguably the true highlight of the film. The fact that he's able to milk an oscar-worthy performance out of Adam Sandler of all people should be a testament to how skilled he is at his craft. Now, this is the first film I've seen by him, and after seeing it I'm dying to see more of his work. This man is a true master of using bright colors to both catch your attention and give the film a sort of surreal, dreamlike look. Although I think I could have done without the seizure-inducing interludes. Nevertheless, this film was still expertly crafted and totally engrossing.
After seeing this film, I'm truly excited to see Paul Thomas Anderson's other films (especially Boogie Nights, which I've heard is excellent). This is definately in my top 5 favorite films of the 2000s, and it's something pretty much anyone can enjoy and relate to. 5/5.