You've all seen it. You know what happens. It's dudefest as shit. DiCaprio is unhinged. Wahlberg is golden. Nicholson is terrifying. Damon is a little bitch. Alec Baldwin is in it. The chick's a slag. Everybody dies. "What, do you got your period?"

Since I'd be wasting my time and your time (but mostly my time because writing takes longer than reading) by going through the plot of the film, I'm instead going to talk about the DiCaprio and Damon characters, Billy Costigan and Colin Sullivan, respectively. They have a lot of shit in common, but they somehow seem to go about said shit in completely different ways. For instance:

They both had mob ties growing up...

Sullivan starting working for Frank Costello when he was a tween, and Costigan had a bunch of mob cronies in his family. In fact, it's implied that Costigan's family, other than his ballin' ass father, was essentially an outhouse: an assorted collection of pieces of shit.

...but no one suspects Sullivan of being part of the mob, because they're too busy suspecting Costigan.

Excuse me? Sullivan owes his whole career to the only man who has fucked Boston over harder than Bill Buckner. Seriously, did no one do background checks, or ask if anyone's extra curricular activities in high school involved cleaning the blood off the most terrifying human being in the Greater Boston Area after watching him execute two people? Oh right, he got good grades in school, so we can overlook that. Oh wait, mob ties and good grades? Right, that describes Costigan too. So why is he in the shitter? Because his family had the mob ties. He wasn't ever hanging out with the mob, his family was. But apparently that's all that matters, because in Boston (trust me, I live here/there) the following equation holds true:

Suspicion raised by family mob ties > Suspicion raised by personal mob ties

They're moles in opposite organizations for opposite organizations...

Sullivan working as a cop to be a mole in the Boston State Police Force for Costello, while Costigan (yeah, they end up hiring him), works his way into Costello's inner circle for the Boston State Police Force.

...but Sullivan lives like a Boston royalty and Costigan is essentially a PTSD victim

Note that when I say Boston royalty, I mean that he has an apartment with wooden floors that DO NOT have nails sticking out of them, and a kickass porch! Dude's like upper class. Well, Boston upper class. All he wanted in life was to see the Massachusetts State House. Why? Who knows. Maybe he likes shiny shit. Or gold. Which is a subset of shiny shit. Which is the way Costigan lives, hold the shiny. Costigan's apartment looks worse than any college apartment, he has panic attacks, he can't sleep, and he lives in constant fear of his own life. And did I mention that he had to go to jail? Well he did. And do you know what happens in jail? If so, shoot me an email, because I don't. But you know what I do know?

Life as a mobster undercover as a cop > Life as a cop undercover as a mobster

They're eskimo brothers...

Obviously they both bang the only chick in the movie who isn't with the terrifying mob boss. And neither of them know who the other one is (kind of like the whole mole thing eh?).

...but Sullivan's dating/engaged to her and Costigan kind of just yells at and bangs her.

Costigan clearly has the better end of the stick here. And I'm not just saying that because Sullivan can't get it up. Costigan spends 90% of his time with this chick being a straight up dick hole (a Candiru, if you will), and the other 10% giving her the business, which is code for humpin', but for whatever reason she's in love with him. Meanwhile, Sullivan's always mopey around her, 10% of the time because he can't get it up, and 90% of the time because he's a little bitch. And she hates him. Why does she hate him but love Costigan? I dunno. Maybe she prefers yelling to brooding. Maybe all women do. Another equation for you, gentlemen.

Sex appeal of verbally abusive men > Sex appeal of brooding little bitches

They both die...

Everybody dies. Except Wahlberg's character (the legendarily vulgar Staff Sergeant Sean "Of Course His Name Is Sean" Dignam), and the chick. And Alec Baldwin I guess too. And the chick Costello was banging. Ok so not everyone dies. But most of the main characters do.

...but Costigan gets the Medal of Merit and a son, while Sullivan gets dick.

Clearly Sullivan was winning in life, chicks aside of course, but Costigan takes the cake in death. He dies a father, a hero, and with the love of the Sullivan's fiancée. He receives a police funeral, and Costello never even found out that he was the mole. Sullivan however, died... differently. Without a son or a woman, he gets killed in his own apartment, after his neighbor wouldn't even let him pet her dog. Harsh. And the dude who killed him? Dignam. In sweat pants. At least he still had that apartment. Little bitch.