10 Film Heroes Who Totally Failed In Their Quest

6. Billy Costigan - The Departed

The Quest

Find the rat in the Massachusetts State Police, bring down mob boss Frank Costello (Jack Nicholson) and safely exit from undercover duties in Costello's gang.

What Happens?

Billy Costigan (Leonardo DiCaprio) finds himself at odds with Colin Sullivan (Matt Damon) over the course of the film, each serving as an undercover agent in the other's respective outfit - the cop Costigan in Costello's gang and Costello's protege Sullivan in the police.

Each spends the bulk of the film trying to uncover the identity of the other, leading to a violent, fateful meeting in the third act.

Why Did He Fail?

Costigan is a classically doomed, tragic hero, and though he does in fact deduce Sullivan's identity, he's unable to do anything about it or make apparent his status as an undercover cop - at least while he's alive.

Sullivan erases Costigan's undercover file from the police's computer system, and as Costigan attempts to bring Sullivan into custody, he's shot in the head by Trooper Barrigan (James Badge Dale), another corrupt cop in Costello's employ.

Sullivan at least gets his just deserts in the end - he's killed by Sergeant Dignam (Mark Wahlberg) in retaliation and it's implied that evidence of Sullivan's guilt may eventually make its way public.

However, Costigan nevertheless suffers the indignity of not only dying but being recommended for the Medal of Merit by none other than Sullivan himself.

Worse still, he never gets to be a father to the baby it's heavily implied he sired with Sullivan's former partner, Madolyn (Vera Farmiga).

Though Costigan deduced the rat, he died and had to let others finish the job. As for bringing down Costello? He never got to take the mob boss out, as Sullivan murdered Costello after learning that he was an occasional rat for the FBI.