I thought this movie was wonderful and I loved the exploration of the brilliant ironic contrast between the Costigan and Sullivan characters throughout the movie:
Where Costigan's desire to join the force is to escape his dysfunctional and tragic upbringing and to bring some form of dignity to his family name and of course the ironic twist of fate where he is placed undercover to play a role of the very man he was determined not to become.
The need to prove his worth leads Costigan to live life dangerously undercover, fearing gravely for his life daily and quickly developing a strong dependency on prescription drugs to deal with the daily stress of violence and crime not to mention the lack of emotional support due to the fact that he cannot delve into the details of his job even to his psychiatrist.
Enters a second character, Sullivan who is brought up and molded from an early age to become an inside man for the mob. He lives comfortably and easily in a wonderful apartment, dining in French restaurants and receiving praise from the Police Department and trusted so openly, allowing him to rise up in the hierarchy of the state police without so much as a raised eyebrow in contrast to Costigan, who's motives are constantly scrutinized by both sides of the law.
The two characters came from the same neighbourhood and had similar upbringing before they took different paths: one of corruption and one of virtue. The strong contrast existing in the result of the two choices are then made evident in the film so beautifully in a single scene: where we cut from Sullivan dressed suavely wooing his date in a fancy restaurant to Costigan in hospital receiving a cast to his hand after a violent bar fight which is to kick start his delicate infiltration into the mob circle.
A fantastically painted contrast.
I enjoyed the film immensely and loved the performances - esp Nicholson's and was impressed with Damon's and DiCaprio's.
However, some elements of the movie drove me up the wall... strangely to a point of pure frustration and annoyance.
I understand that when elements in a movie's plot don't necessarily make sense you can simply argue that it is "just a movie" and that the ficticious nature of Movies versus Documentaries means having loose ends and plot holes, but in terms of the movie The Departed... once you look at the all-star cast and the profile of the director - I just find this outlook to be a slight cop out.
I found this movie to rate highly amongst other Scorsese films... I just actually thought the movie could have been even greater than what it was.
BEWARE SPOILERS: READ WITH CAUTION PLEASE
I found it confusing why Costigan didn't just confront Sullivan when he found the "CITIZEN" envelope in his files in the office and chose to leave instead and then later asked Sullivan to meet on the rooftop for a confrontation... could it be he didn't think he would be believed by the members of the force? ... Then why did he ask the guys on the force (Brown) to back him up when he made the "citizen's arrest" on the roof top? Couldn't he have just confronted Sullivan and asked the PD to contact Wahlberg's character Dignam to confirm his identity right there in the office?
I find it comical to believe that Dignam would have left Costigan alone undercover after Queenan's death without trying to contact him.
I also don't quite see why the second mole didn't just let Sullivan take the fall for him... if he feared Costello had given them up to the FBI why bother killing off Costigan and Brown and digging a deeper hole for himself? Bit silly.
The whole "yellow envelope" exchange between Costigan and Madolyn also doesn't quite make sense, it was later never mentioned... you may elude to the fact that it could be a plot device known as a Macguffin - but that would fit if the envelope allows the plot to be somehow furthered, but it doesn't. The story would have still held if the envelope exchange scene was omitted.
I thought that the envelope would be paving way for a final TWIST provided by the Madolyn character and therefore validating the presence of the link Madolyn provided between the Costigan and Sulliven character... but the twist never came and I was left wondering why they even bothered having Madolyn link the characters in the first place, except of course for it to add another touch of irony to the plot. hmmmm...
Still a great movie, I enjoyed it - that is if I don't think too much into it... but where's the fun in that?