Wolf Moon
Chris and his family move to Beacon Hills in between semesters of Allison's sophomore year in 2011. It's unclear whether Chris and Victoria previously lived in Beacon Hills, or whether his sister Kate lived there on her own for a time. They moved into town before Laura Hale was killed, making it, apparently, coincidence that they arrived just as a Werewolf problem was developing.
Chris and two hunter goons first appear, attacking Derek and Scott in the woods. Chris shoots a young werewolf in the arm with a bolt from a crossbow, pinning him to a tree, but Derek frees him before the hunters can get any closer. When Chris sees Scott with Allison at school the following day, he does not recognize him as the young beta that he shot.
Second Chance at First Line
The next time they meet, Scott had been up on the root outside Allison's window, watching her while wolfed out. When Scott jumps down off the roof and starts to leave, Chris hits him with his car by accident. Scott goes tumbling over the hood but comes away unscathed. Chris is confused about how this can be and takes the opportunity to invite himself to Scott's lacrosse game that night.
As the game progresses, Chris keeps an eye on Scott, presumably trying to determine if there's anything weird up with him. He seems to come to the conclusion that Scott must be a werewolf, but he doesn't act of this intuition for a very long time.
Pack Mentality
Largely, his biggest concern is as the father of a teenage daughter who just got her first boyfriend. The night of Allison's bowling date with Scott, Lydia, and Jackson, Chris informs her that she's not allowed to leave the house because of the curfew the police have put in place. He leaves Allison and Lydia to their own devices and doesn't seem to notice when they both leave the house.
While Allison is at the bowling alley, Chris rounds up some hunter goons and seeks out Derek. They find him at a gas station, where Chris proceeds to threaten him by cleaning the Camaro. He tells Derek that he's very protective of the things he loves and then tests him by prodding him about the deaths of his family. Derek doesn't react violently, so Chris assumes that his point is made. When Derek mouths off, though, Chris allows one of the hunters to break one of the car's windows. The meeting serves to inform Derek that they know who he his, what his history is, and that they can find him if they want to.
Magic Bullet
Chris's sister, Kate, returns to town to help with the hunt for the alpha. She doesn't even make it to their house before she's shooting at Werewolf, and Chris goes out to find her, instead. Allison catches him while he's leaving in the middle of hte night, and he tells her that Kate got a flat. He meets her in the warehouse district and immediately tells her to put her assault rifle away before someone sees them. He orders her to stop trying to kill the betas, because they won't be able to lead them to the alpha if they're dead. Annoyed, he asks her how long the one she shot has to live, and she tells him 48 hours.
Kate and Chris fail to coordinate their stories about what was wrong with her car, giving Allison the first clue that someone is lying to her.
The following day, Scott comes over to study with Allison, which quickly turns into a makeout session. Chris catches them together in the garage and orders Scott to help bring in the groceries and then leave. He doesn't approve of Scott getting intimate with his daughter, but Kate steps in and tells him to chill out. She invites Scott to stay for dinner despite Chris's objections. He spends the dinner grilling Scott, testing him about drugs and alcohol and trying to make him uncomfortable. He's so heavy handed that Allison gets angry, and Scott tries to ease the tension.
Still not satisfied, Chris tries to determine if Scott is a Werewolf by telling him a story about having to put down a rabid dog. "Something that out of control is better off dead." But Scott doesn't give himself way. Later, when Scott is about to leave, Kate accuses him of taking something from her bag. Chris comes to see what they confrontation is over and is distressed to learn that Allison took a condom from Kate's things.
After dinner, he and Kate discuss their strategy for finding the alpha. Chris thinks that Derek will lead them to him, if they can just be patient and not kill him. He insists that they hunt according to the Code and not just kill every Werewolf for the hell of it.
The Tell
Allison's birthday is the same day as the Beacon Hills High School parent-teacher conferences, and the first day Allison has ever skipped class. Chris and Victoria learn about this from her English teacher, and they are livid to learn that they don't have the "open and honest" relationship with their daughter that they thought they had. At least, open and honest from her side. They confront Scott's mom outside the school and accuse her of being a bad parent for letting Scott corrupt their daughter. Before Melissa really has a chance to defend herself, Scott and Allison show up from their day in the Beacon Hills Preserve. The parents start yelling at their kids, but it's quickly apparent that there's something wrong in the school parking lot, because people are running and screaming.
Chris goes to get his pistol from his car and ends up shooting a cougar.
Lunatic
Following the night at the school with the alpha, Chris becomes even more protective of Allison. He doesn't want to let her go to school the following Monday and checks out the school building warily. Kate ribs him for overreacting, but once Allison is out of the car, he tells her that he's come around to her way of thinking. They should have taken more forceful action against the Werewolf. That night they plan their next move. According to Chris, an alpha is just as out of control on a full moon as any other Werewolf, which should make it easier to catch because it will have a difficult time planning and being focused.
The Argents end up in the woods watching the police wrap up another murder scene. They spot Stiles there talking to his dad, and they become suspicious that he might be the younger beta.
Wolf's Bane
Chris remains determined to take out Derek now that he's decided that Derek isn't going to lead him to the alpha. While the police are chasing Derek through the ironworks trying to apprehend him for the murders around town, Chris closes in on him. He follows Derek into one of the factories and uses a flash bomb arrow on him to stun him. He misses a few times with his crossbow and then takes out an assault rifle instead. Scott and Stiles pick Derek up in the Camaro before Chris is able to really do any damage, though.
The following day, Scott went into Allison's room to steal her necklace. Chris finds him outside just as he was leaving and invites Scott in for a talk. He offers Scott a beer, and Scott again refuses, telling him that he can stop testing him because he and Allison are broken up. Chris instead asks him about Derek. Scott gets defensive and claims not to understand why it feels like he's in trouble. Chris confides that he's only worried about Allison's safety, and Scott claims that that's all he ever thinks about as well. Chris lets Scott leave so he isn't late for his game.
Chris, Kate, and Allison attend Scott's game, and Kate notices the scratches on Jackson's neck. She asks Chris if someone can be turned by a scratch instead of a bite. He allows that a deep enough scratch might do it, and they now suspect Jackson of being the second beta.
Co-Captain
In order to test their theory, Chris puts a device in Jackson's car that makes his engine stall. He follows him into the warehouse district and then pulls up to offer assistance when Jackson's car dies. Chris insists that he's good with machines and that they might be able to figure out what's wrong if they just look under the hood. He leads Jackson around to the back of the Porsche and pops the hood. When he gets Jackson to lean in for a look, Chris checks out the wounds on the back of his neck.
Scott and Stiles pull up before Chris has a chance to do anything else. When no one is looking, he grabs his device back and starts the car. Chris leaves before anything starts to seem too suspicious.
Formality
The night of the dance, Chris, Tyhurst, and a red shirt are in the woods by the school looking for Werewolf. They find Jackson instead, and Jackson tells them that Scott is the second beta. The hunters corner Scott outside in the parking lot, trapping him between some buses and their cars. They try to crush him, but Scott jumps up and lands on the hood of the SUV instead. Chris yells at him to move, and Scott runs for it. Allison saw the whole thing, so Chris backs up his truck so she can get out of the bus and then catches her in his arms before she collapses to the ground in shock and tears.
Code Breaker
He takes her home, and it's clear from some conversation they have that Allison is aware of werewolves thanks to Kate. Chris rages at his sister. She made sure that Allison would learn the truth about Werewolf and their family, despite Chris's desire to keep her in the dark awhile longer. He orders Allison and Kate to go to a house they have in Washington.
After they leave, Chris, Tyhurst, and the red shirt go to the hospital to find Stiles in the hopes that it will help him find Scott. Stiles is snarky and unhelpful, but he does accuse the Argents of having burned down the Hale House. When Chris denies any involvement because it would break the Code, Stiles asks him what happens when someone doesn't follow the Code. He tells him that Kate burned the house, and Chris believes him. He heads to the Hale House in search of his sister.
Chris: "We go by the Code. Nous chassons ceux qui nous chassent."
Chris orders his Kate to put down her gun or he'll put her down. A disbelieving Kate complies.
Peter Hale shows up at the house, as well, and knocks Chris out of the fight early. He doesn't come to until Kate is already dead and Peter is burned and nearly dead also. As he watches, Allison kisses Scott despite now knowing he's a werewolf. He is exasperated at this, but witnesses Derek Hale kill the Alpha, Peter Hale afterward.
The Argent set up the crime scene depicting that Kate really was responsible for the Hale House fire. Once the story hits the Beacon Hills Chronicle, Victoria reminds her husband that Katelivid that she should take the fall for something she didn't do. Chris is more concerned that their reputation in the town will be ruined and whether Allison can handle everything now.
A few days after everything goes down, Chris catches Scott and Allison at one of their rendezvous. Furious, he holds Scott at gunpoint, with his sidearm in the young man's face, threatening to shoot him right there and then. Terrified, Allison hurriedly and tearfully begs her father to spare Scott, that she'll do whatever he wants her to do, swears she'll never see Scott again, and pleads repeatedly. Chris relents, letting Scott go. He strictly emphasis: "Never again."
Chris also gives his word,he will keep Scott's name away from anyone dangerous, but solely for Allison's sake.