Matt Murdock (BEN AFFLECK) is a blind lawyer who, with his legal partner, Franklin "Foggy" Nelson (JON FAVREAU), helps the innocent in New York City's Hell's Kitchen by day and seeks vengeance on those who've eluded justice by night. He does so in the form of his alter-ego, the mysterious and acrobatic Daredevil, a figure who's drawn the attention of newspaper reporter Ben Ulrich (JOE PANTOLIANO).
Long ago, 12-year-old Matt (SCOTT TERRA) was accidentally blinded by a chemical spill. It left his remaining senses, however, super-enhanced, including the ability to "see" with something akin to radar vision. When his pugilist father, Jack (DAVID KEITH), was murdered by his crime boss for not throwing a fight, Matt vowed to fight for the little guy and right all of the wrongs that he could.
Yet, his vigilantism has created mixed feelings in him, resulting in him often spending time in a church's confessional. That is, when he's not pursuing Elektra Natchios (JENNIFER GARNER), a beautiful young woman who's just as proficient at martial arts as he is. The fact that her father, Nikolas (ERICK AVARI), has business dealings with Wilson Fisk, a.k.a. Kingpin (MICHAEL CLARKE DUNCAN), and wants to get out of them soon puts all of them in danger.
That's because Kingpin has sent his highly proficient assassin, Bullseye (COLIN FARRELL), to kill Nikolas. Soon, Elektra's life is in danger as well and it's up to Daredevil to save her. From that point on, the masked avenger must contend with all of that, his possibly outing by Ben, and all of his pent-up and conflicting emotions about what he does and who he is.