Matt Murdock and Foggy Nelson open their law firm, and take the case of a woman accused of murder who Matt believes is innocent.
- In 1994, boxer "Battlin' Jack" Murdock races to the scene of a traffic accident, to find his nine-year-old son Matt (Skyler Gaertner) amidst the wreckage of an overturned truck carrying chemical waste. Matt saved an old man from being hit by the truck by pushing him out of the way, but in the process his eyes were splashed with chemicals that blind him, and Jack is left to comfort his now-disabled son.
In 2014, Matt Murdock (now played by Charlie Cox) visits the Hell's Kitchen church his father attended and takes confession. He tells the priest, Father Lantom (Peter McRobbie), about his father's record as a "tough as oak" boxer, and how sometimes Jack would "let the devil out" on his opponents. Matt didn't understand what that meant at the time, but he does now. When Lantom asks what Matt has done that he wants to confess, Matt admits that he doesn't want forgiveness for what he's done, but rather what he's going to do.
That night, at the docks, a gang of human traffickers, lead by Turk Barrett (Rob Morgan), are loading captive young women into a shipping container. Matt, wearing a black suit and mask that hides his identity, carries out a surprise attack on the traffickers, using his heightened senses and advanced martial arts to dispatch each one of them with ease, and frees their captives.
The next morning, Matt is aroused from his sleep by a wakeup call from Foggy Nelson (Elden Henson), his best friend, fellow lawyer and new business partner. Foggy is calling to remind him that they're scheduled to meet with a realtor to scout out potential office space for their new firm, Nelson & Murdock. After Foggy hangs up, he goes to a subway entrance, where he meets with Sgt. Brett Mahoney (Royce Johnson) of the New York City Police Department's 15th Precinct. After a bit of casual banter about how they're technically enemies (despite having been friends since they were kids), Foggy bribes Brett with a bag of cigars for his mother in exchange for information on any hot cases.
Matt and Foggy meet up at the office space, and their realtor, Susan Harris, guides them around. The space is relatively modest - a reception area, a conference room, and two offices, and a view of the Hudson from the corner suite. It's on the market right now because it's one of the few buildings in this part of Hell's Kitchen that wasn't touched by "the Incident" (apparently, that name is a lot better than "death and destruction raining from the sky nearly wiping Hell's Kitchen off the map"). Matt decides to settle on the space, and Foggy reluctantly agrees, despite his reservations about the location. Now they only need clients, but that's been difficult due to Matt's insistence they only defend the innocent; at this point, they'd settle for a single client.
That first client comes in the form of Karen Page, a woman found in her apartment by police, standing over a dead body and holding a bloody knife, and arrested despite her tearful pleas of innocence. That night, Brett calls Matt and Foggy to tip them off. Matt and Foggy go to the precinct, where they are escorted to an interrogation room by the investigating detectives Christian Blake (Chris Tardio) and Carl Hoffman (Daryl Edwards). They are able to convince Karen to hire the firm and be their first client. In tears, Karen explains that she and the victim, Daniel Fisher, worked for a construction firm called Union Allied, and after meeting up for drinks the night before, she blacked out and woke up in her apartment a moment before the police arrived. Matt's super-senses let him know she's telling the truth.
The next day, a middle-aged corrections guard named Clyde Farnum is eating lunch in Abe Lebewohl Park when another man in a suit and tie walks up and sits down next to him. This is James Wesley (Toby Leonard Moore), the right-hand to a mysterious mob boss. Wesley explains that his organization has acquired the $30,000 debt that Farnum owes to Rigoletto, a mobster who has recently "retired". He then shows Farnum a live tablet image of his daughter Tracy in a park, with an assassin stationed not ten yards away from her, who they are going to give a kill order to if Farnum doesn't use his position to do a job.
Meanwhile, at the Nelson & Murdock office, Matt is beginning to think something's amiss: if the case against Karen is so open-and-shut, why haven't the police formally charged her or publicized the arrest? Foggy suspects Matt's reluctance is because Karen is just his type (a beautiful woman of "questionable character"), but he agrees to dig deeper into the matter.
In the middle of the night, Farnum attacks Karen in her cell and tries to strangle her using a bedsheet tied into a noose. Karen fights back, clawing at Farnum's face until she draws blood from one of his eyes. With Farnum overpowered, she screams for help. The next morning, Matt and Foggy sit down with Detectives Blake and Hoffman to demand Karen's immediate release. They know full well that something's going up, as the cameras in Karen's detention area were disabled right before the assault, and the detectives have failed to charge her within the legal time limit. Matt suspects the attempted murder was part of an attempt to cover up evidence that would exonerate Karen. Blake and Hoffman take offense at the lawyers' attitude, but reluctantly agree.
Matt and Foggy take Karen back to their office. They remind her that just because she's been released doesn't mean she's off the hook yet. While she drinks some tea to calm her nerves, Karen admits to knowing why someone would want her dead, although she doesn't know who. She explains that Union Allied has profited from securing the majority of the federal government's contracts to rebuild much of Hell's Kitchen. Karen worked as a secretary in charge of overseeing the pension funds. One day, she had accidentally been copied into the email of a "pension file", which was actually a ledger for what Karen suspected was criminal activity. Her boss laughed off her concerns, so Karen asked Daniel Fisher from the legal department, to advise her on what to do next. When they met up to discuss it, someone drugged their drinks, moved the two back to Karen's apartment, then stabbed Fisher to death and planted the bloody knife in Karen's hand. Karen blames herself for Fisher's death, and tearfully insists on leaving, not wanting Matt or Foggy to suffer because of her, but the pair resolve to keep her safe, and Matt offers to let her stay at his apartment.
Matt takes Karen back to his apartment. It's large, but it's also sparse and very cheap, in part due to a bright and gaudy electronic billboard on the building across the street (Matt has to dissuade Karen from taking the couch as a result). Over coffee, they talk about his blindness, and Matt admits that he misses his sight. Their talk turns to the Union Allied business, and Matt proposes his theory: the reason Karen wasn't killed right away, but just framed, was because she has something the conspirators want. Stabbing a fellow coworker to death in her apartment was just to scare her and discredit her. However, something went wrong - either something going wrong while staging the crime scene, or two lawyers showing up before the conspirators' representatives could get to Karen - and that's when they resorted to attempting to kill her. Matt thinks that the conspirators believe Karen kept a copy of the pension file. Karen denies it, but Matt senses the lie.
A disparate group of organized criminals meet on the roof of a partially-constructed building: elderly financial expert Leland Owlsley (Bob Gunton), Russian mobsters Anatoly and Vladimir Ranskahov (Gideon Emery and Nikolai Nikoleff), Yakuza enforcer Nobu Yoshioka (Peter Shinkoda), and elderly Chinese drug manufacturer Madame Gao (Wai Ching Ho). Wesley is the last to arrive as a representative of his employer, though he refuses to allow his boss's name to be spoken aloud. When Wesley asks why the Russians are short on their payments, they explain that a shipment was stopped by a masked vigilante in black. Owlsley is dismissive, more concerned with the Union Allied situation, but Wesley assures them the matter is well in hand and is more interested in the lone vigilante.
In the middle of the night, Karen sneaks out to her apartment to retrieve a flash drive containing a copy of the pension file. Rance is waiting and attempts to kill Karen after taking the drive, but Matt has followed her in his vigilante outfit, and fights Rance. Bolstered by memories of his father, Matt defeats the assassin and retrieves the flash drive with Karen looking on, though she doesn't recognize him. He promises to get the drive into the right hands, bypassing the cops, and telling "everyone" by delivering the assassin and the flash drive to the offices of the New York Bulletin.
A few days later, the Union Allied story is front page news in the Bulletin. While reading the story in the paper, Wesley talks on the phone with his employer, Wilson Fisk (Vincent D'Onofrio), and assures him that the scandal won't be linked to their operation, since Owlsley has cleared out the dirty money and the key people with evidence, such as Clyde, Rance, and Karen's boss, have been or will be dealt with. Farnum is shot in his basement and his death staged as a suicide, Rance is hanged in his jail cell with a bedsheet, and Karen's boss is force fed a lethal dosage of pills. Fisk is curious about how Rance was subdued, but tells Wesley to leave Karen alone, since she doesn't know anything beyond what has already been exposed, and to keep an eye on Nelson & Murdock in case they'll be useful in the future.
Karen cooks Matt and Foggy a celebratory meal to celebrate her acquittal, and offers to repay them by becoming their new secretary. Despite the firm's victory, the criminal enterprise is continuing unabated. That night, Matt waits on the rooftops of Hell's Kitchen in his vigilante suit and listens for trouble; hearing the sound of a child being abducted from his father by the Russians, Matt pulls on his mask and goes to work.