The film details the true story of undercover agent Joe Pistone, aka Donnie Brasco, who infiltrated the Mob in the 1970s. Brasco (Johnny Depp) befriends and gains the confidence of Lefty Ruggiero (Al Pacino), an aging wise guy who never made it to the top of the local gangster hierarchy. He sees his relationship with the street smart Donnie Brasco as his ticket into the big time, not realizing it will bring him his demise. Lefty takes Donnie under his wing and teaches him the ropes of the cruel game they play. After they rob and beat up a club owner, Donnie pays for his drink. Lefty questions him: "Why did you pay for that drink? A wise guy never pays for his drink." Lefty unknowingly teaches him how he should act in order to survive this dangerous mole operation.

Donnie is soon faced with a moral dilemma: He is divided between abhorring Lefty and feeling empathy for him. An unexpected father/son relationship has developed between Donnie and Lefty that cannot be reversed. The fact of the matter is that Donnie truly cares about Lefty. He feels sorry for him. And who wouldn't? Al Pacino's character is so pathetic as he sits in his crappy little apartment with his loyal wife and worries about his junkie son. He only wants what we all want: A better life. Lefty mentions that if he had a boat, he would sail away from this life and live in simplicity. Donnie seriously begins to think of putting his job on the line so he can grant Lefty's wish. Hence, a tender and touching Mafia movie. Donnie is in a no-win situation. His inevitable betrayal will hurt him as much as it hurts Lefty.

The longer Donnie is involved in the Mafia lifestyle, the more he assumes his fabricated identity. It's of the utmost importance that he doesn't slip. The slightest mistake could cost him his life. He must prove his loyalty to the Mob by committing and witnessing crimes. (The real Donnie Brasco lived this life for seven years.) At the same time, Donnie must cut off his relationship with his family in order to protect them. He straggles in at odd hours to a worried wife and angry children. At one point, his wife comments on how he is turning into the criminals he is pursuing. He says, "I'm not becoming like them, I am them." We realize that Donnie and Lefty are more alike than not. They are both cogs in a futile machine of justice and loyalty.

Donnie Brasco is truly a fascinating take on the Mafia scene. Director Mike Newell has humanized these normally sketchy characters and has exposed the emotional code of Mafioso loyalty. In essence, he has brought us a gangster film that we can really sink our hearts into.