Derek gives Jackson what he wants and bites him. Somehow, Jackson ends up in a river in the preserve, and rises to the surface with his shirt all torn. A couple of days later, while in Chemistry class, Jackson's nose begins to bleed black blood. He runs to the bathroom, and the ooze starts to come out of his mouth, too. Someone knocks on the stall door, and Jackson thinks it's Danny coming to check on him, but it's actually Derek. He could tell that something was wrong and came to check on Jackson. Jackson informs him that he's not going to be part of his pack, but then Derek points out that there's black ooze coming out of Jackson's ear. Derek tells him that his body is rejecting the bite and vanishes, looking terrified. 

 

When Jackson goes home that night, he lies in bed coughing, still choking out more black ooze. His bedroom is littered with tissues. The next evening, while he's throwing away the tissues, Jackson sees Isaac running away from his father after one of their fights. Jackson scoffs and calls them freaks.

 

The next school day, the Sheriff pulls Jackson into the principal's office to talk to him about the Laheys now that Mr. Lahey has been murdered. Jackson admits to knowing that Isaac was abused but not saying anything to anyone about it. Sheriff Stilinski gives him a disgusted look before saying “…it’s funny that the kids getting beaten up are always the ones that least deserve it.” But Jackson doesn't see what the problem is with his choice.

 

When Lydia tries to later thank Jackson for saving her life at the winter formal, he tells her in no uncertain terms that they aren't getting back together. He tells her not to go to the game because it's a full moon.

 

That night, Jackson has Matt bring him a video camera so he can record himself while he sleeps. He wants to capture video of himself shifting. Matt thinks he wants to record a sex tape, and Jackson informs him that he wouldn't do anything so lame. He puts the money in Matt's pocket and takes the camera. He sets it up pointed at his bed and goes to sleep. When he wakes up the next morning, he rushes to see what the camera recorded, but it's just him sleeping. He throws the camera on the ground in frustration.

 

The next day in bio class, Matt yells at Jackson for the cracked lens in his camera. Jackson does care and is actually paying attention to the video they're showing in class on immunity. He thinks Lydia somehow made him immune to the Bite and yells at her after class.  She has no idea what he's talking about. Jackson goes to the Hale House looking for Derek to get answers about why his body is rejecting the Bite, but instead he finds Chris Argent and some hunters. Jackson ends up at the high school doing lacrosse exercises. His truck gets stuck in the mud, and he takes out his frustration on it by trying to push it. He manages to lift the back of the truck out of the mud. 

 

Jackson ends up asking Danny for help with the video he took of himself. He asks Danny to boost the quality, even though there's no indication that there was anything wrong with the quality. He makes Danny promise to keep it to himself. Danny doesn't, and at the lacroose game later, he walks up to Jackson with Matt in tow. Jackson is angry that Danny got Matt involved, but they both point out that Matt's the one who found that the video had been tampered with. 

 

During the game, Jackson starts fighting with Scott because Scott isn't using his werewolf powers to help them win. Scott says he can't because Gerard Argent is in the stands and will see him and know that he's a werewolf. At some point during the game, Jackson disappears.

 

A few days later, Jackson and Danny are in the boys locker room working out. Jackson is convinced that he should be able to lift a lot of weight because supernatural things are happening to him. He keeps asking Danny to add more weight, and Danny tells him the only way he could lift it is if they were on the moon. Jackson insists, and Danny decides he's had enough. He goes to take a shower and tells Jackson that if he's dead when he comes back, he's taking the Porsche. Jackson attempts to lift too much weight anyway, and the bar goes down to his chest. Erica lifts the bar back up with one hand and kidnaps him.

 

Erica takes him to Derek's subway tunnel hideout, and she and Isaac hold him down. Derek looks very threatening with his black leather gloves and asks Jackson what happened to him on the full moon. Jackson insists that nothing happened and claims to have the video to prove it. They all laugh at the idea that he videotaped himself. Derek says that he has a better way to find out whether Jackson is the kanima and he comes at him with a piece of the mirror that Scott used to scare the kanima away. There is paralytic venom on the glass. Erica and Isaac hold Jackson's mouth open, and Derek feeds him a drop of venom. Jackson gets paralyzed, much to their annoyance. While Jackson is unable to move, Isaac tells him that he's going to recant his story with the police about seeing the Laheys fight, which will get suspicion off of Isaac and allow him to come out of hiding. 

 

The next morning, Jackson tells Sheriff Stilinski that in fact he did not see Isaac and his father fighting the night Mr. Lahey was murdered. Later that day, Danny tells Jackson that he found a program that can recover the lost video but it will take a while to run. He will run it during their free period. Jackson then overhears Isaac and Erica planning to do something to Lydia during Chemistry class. In Econ, Jackson asks Stiles and Scott what a kanima is and why Derek thinks he is one. He tells them that he overheard Isaac and Erica talking about Lydia. Coach Finstock notices the three of them talking and asks Jackson if there's something he'd like to share with the class. Jackson compliments Coach, and Finstock thanks him and tells him to shut it.

 

Jackson meets up with Danny in the library for free period so Danny can run the video recovery software. Matt joins them, and Jackson just watches as the two of them flirt. He makes fun of Danny for it, but Danny tells him that Matt is interested in Allison. Danny asks Jackson if there's anyone who could get into his house to edit the video, and as he says it Lydia walks into the library.

 

Allison, Stiles, Jackson, and Lydia leave the library and go to Scott's house, because Derek and his pack are convinced that Lydia is the kanima. When they get to the house, Jackson takes Lydia upstairs and asks her for his key back. She yells at him for being insensitive, but he asks her a second time. She says she doesn't have it, but he can tell she's lying. Jackson then accuses Lydia of being the one to edit the tape. He doesn't understand why she always wants to take everything from him. They both get upset, and Lydia takes the key and chain from around her neck and gives it back to him. She cries, and he can't stand to see her cry, so he kisses her. They break apart when they hear crashing and fighting downstairs. Lydia goes to look, but Jackson collapses in pain. When Allison arrives at the door and tells Lydia to hide, Jackson is gone at the window is open. 

 

When the fighting is done, everyone is outside except Lydia. They all see the kanima crawling along the roof of Scott's house, and then Lydia comes running out the front door. Scott realizes that Jackson is the kanima after all, although Derek does not.

 

Derek takes off after the kanima on foot, while Scott and Stiles take Stiles's Jeep. They follow it to the warehouse district, where Derek fights it hand to hand. He does okay until the kanima pulls out some electrical wiring, and the flashes blind him. Chris Argent shows up and fills the kanima with bullets, although he's really there for Derek. He thinks the kanima is dead, but it gets up and throws him into a wall. The kanima then goes to Gerard Argent and stares at him awhile without attacking. Scott tackles the kanima, which sends it running.

 

It heads for the Jungle because Danny is going to be there and crawls in through a window on the upper floor. It crawls along the ceiling, and while concealed by a smoke machine, drops down and starts knocking people out, including Danny. Derek appears and attacks it, slashing its throat deeply. The kanima takes off out the back and shifts back to Jackson in the parking lot. Scott finds Jackson with blood on his throat, naked, between some parked cars. He and Stiles get him into the back of Stiles's Jeep and attempt to keep the police from spotting him until they can get him out of there. Scott has to punch him to knock him out and keep him from making noise.

 

When Jackson wakes up, he's chained in the jack of a prison transport van. He immediately thinks it's Stiles and Scott's fault. Stiles goes into the van to bring Jackson some food. He explains that he put Jackson's clothes on him, so this hasn't been a fun time for him either. He tells Jackson that he's been turning into a monster and killing people, but Jackson obviously thinks he's crazy. Jackson tells him that his parents will be looking for him, and Stiles reveals that he's been using Jackson's phone to text his parents.

 

In an effort to convince Jackson that he's been killing people, Stiles asks him what he did on the night of semi-final game. Jackson claims he went home. Stiles explains that in fact he tried to kill him and Derek at the pool. He also tells Jackson that he tried to kill Danny, and Jackson wants to know why he'd try to kill his best friend. Stiles has no answer. Jackson threatens to prosecute them both.

 

Later that night, Jackson listens as Allison, Scott, and Stiles discuss what to do with him. Stiles suggests killing him. Scott won't hear that. He sympathizes with Jackson, beacuse when he got the Bite, he didn't know what he was doing either, but he had people to help him. Jackson has no one. A tear runs down Jackson's cheek when they talk about how alone he is. His skin starts to shift into scales. Jackson continues to change and eventually breaks out of the prison van while no one is watching.

 

The kanima goes to attack a man named Sean and his wife in their trailer home in the woods. It drags Sean into a tree and kills him and then goes for the wife. The wife is pregnant, and the kanima stares at her belly before running away, unable to kill her. 

 

After the killing, Jackson goes home to wash off the blood and then to his parents and the police to get a restraining order against Scott and Stiles. 

 

The next day at school, Jackson goes to the biology lab to discuss his paper. He is enthralled by a snake in its cage and lifts it up. It crawls around his arm and down his throat. Presumably this is a hallucination. Later, he goes to the boys locker room for a shower. When Allison comes in looking for him, he calls to her, but he's not acting like himself. He doesn't warn her that he's naked and uses her discomfort against her, backing her up against the wall as he talks. He asks her if she's stressed about her relationship with Scott and tells her that she's a stupid bitch if she thinks he's not going to eventually go run to Derek's pack. Being in love won't save her. He takes out his claws and touches her face, telling her that he hopes her dad has been teaching her to defend herself. She replies that he has and grabs his wrist and tries to throw him. It ends up with her on the floor and Jackson on top of her. Jackson is shocked back to himself and has no idea what he's doing or why Allison is there.

 

Scott bursts in to find them like that. He attacks Jackson, and the two of them fight, ruining the locker room and breaking a sink. Jackson throws a 45lb weight like a Frisbee. When they tumble out of the locker room into the hall, Erica restrains Jackson, while Stiles takes Scott. They all get detention.

 

In detention, Jackson tells Mr. Harris that he's not allowed to be close to Scott and Stiles. Mr. Harris moves them one table further away. Jackson starts getting one of his headaches during detention and asks to go to the bathroom. As he looks in the mirror, a snake bursts out of his eye socket and slithers down the drain. Jackson goes back to the library looking worse for wear. Mr. Harris leaves but tells them all they have to stay and restock books.

 

While putting books away, Jackson starts seeing messages written on the spines: Close Your Eyes Jackson. Close Them Now. He shifts in the library and knocks out Matt. Half-transformed, Jackson ruins the library and then goes to the blackboard. He writes: STAY OUT OF MY WAY OR I'LL KILL ALL OF YOU, then leaps out a window and escapes. 

 

Jackson is back at school the next day and gets a text message during class. He leaves and drives to somewhere in the warehouse district. The rave on Friday is selling tickets only from this location. Jackson runs into Matt, who is nervous to see him and lets him cut in line. Jackson steps up to the ticket window and holds up a single finger to indicate how many tickets he wants. He doesn't say anything, and his creepy stare makes Kara Simmons, the ticket seller, end that day's sales. 

 

Everyone seems to know that Jackson is going to be at the rave on Friday, so they all attempt to capture him there. He heads straight for Kara, but Isaac and Erica intercept him and start dancing with him and kissing him. It's meant as a distraction so Isaac can inject him with ketamine. Jackson's master is onto their plan, though, and has Jackson attack them before Isaac can do the injection. Isaac manages to recover the needle and go after Jackson, knocking him out.

 

They drag Jackson to a side room and set him up in a chair. Stiles arrives, and Isaac wants to test if Jackson is really knocked out. He tries to attack him, and Jackson grabs his wrist and hurts it without ever looking conscious. Stiles starts asking the kanima's master questions through Jackson. The master claims that all the people they've killed have deserved it because they murdered someone. When Stiles asks who, they reply: me.

 

Jackson starts to change into the kanima. Isaac already used all the ketamine, so they have no choice but to run. They slam the door on the room shut hoping to keep him in, but the kanima breaks through the wall and goes into the rave. It kills Kara. It's unclear whether or not trying to capture the kanima and master with a circle of mountain ash would have worked, because Stiles has to break the circle in order to allow Derek to save Scott. The kanima and master both escape. 

 

A few days later is Lydia's birthday.  She runs into Jackson at school and asks him if he's coming to her party. He tells her that she doesn't want him there, but he ends up going anyway. He drinks some of the punch laced with wolfsbane and ends up having a hallucination about his birth parents. He sees them from behind and hears them asking to see him, but when they turn around, their faces are blank skin. Jackson feels his own face turn into a blank slate and freaks out about not having an identity. 

 

Everyone at the party starts freaking out. Someone throws Matt into the pool, and he screams that he can't swim. Jackson pulls him out. When the cops arrive to break up the party, Scott sees Matt outside with the kanima wrapped around his legs. Scott realizes Matt is the kanima's master.

 

It's now revealed that when Matt loans Jackson the camera to film himself, he stayed up all night in his car watching a streaming feed from the camera. He saw Jackson change and saw the kanima come up to his car. They made a connection that night. 

 

Matt knows he's been found out, so he follows Scott, Stiles, and Sheriff Stilinski to the sheriff's station. He uses Jackson to incapacitate Derek when Derek arrives to talk to Scott and then has him paralyze Stiles as well. Matt leaves Jackson to watch over Stiles and Derek while he takes Scott into another room and explains how he was killed and why he's been getting revenge. Matt found out that he could control Jackson just by taking a picture of whoever he wanted to die. 

 

The Argents arrive at the sheriff station because Matt told them that Derek was there when he asked for the bestiary, and they want Derek. During the fight, they end up having to fight the kanima as well. Chris and Allison go after it. It attacks Chris, and Allison shoots it in the head with a crossbow. It just pulls the bolt out and comes after her. She hides under a desk and switches to her ring daggers. Allison attacks it and sinks the dagger in, but it doesn't do any good. The kanima grabs her by the throat and then paralyzes her. Chris makes some noise as a distraction and then picks her up and escapes.

 

Matt and the kanima escape the sheriff's station but encounter Gerard at the river. Gerard drowns Matt and takes over as the kanima's master.

 

A couple of days later, Gerard and the kanima go to Scott's house and take his mother hostage. Gerard tells Scott that either he does what he says or he'll kill her. 

 

Jackson returns to school and to lacrosse practice. Isaac tells Scott that Jackson is playing in the championship game, and Scott knows this can't be good news. The night of the game, Danny asks Jackson if he's okay because he hasn't been responding to his texts. Jackson snaps out of his trance long enough to tell Danny to stay in the goal and not come out. He has to run if he sees Jackson coming toward him. 

 

At the game, Gerard tells Scott that he needs to hand over Derek or Jackson is going to start killing people. Scott starts enacting his own plan to get himself into the game, and Gerard has Jackson attack Isaac to get him off the field. When the game ends, Jackson starts to turn but he doesn't attack other people. He rips his own guts apart and collapses.

 

By the time the EMTs get to him, Jackson is dead. They put him in a body bag and wheel him to the ambulance. They don't notice the kanima toxin leaking out of the bag. Melissa McCall rides in the ambulance and takes Jackson down to the morgue. She notices the ooze coming out of the bag and decides to open it. Jackson is encased in a clear cocoon, and his hands are turning into claws. She calls Scott and tells him he needs to get down there. Scott and Isaac arrive, and while they're there, Jackson starts to move. His mouth pops open revealing rows of black teeth. Melissa zips the bag back up, and Scott calls Derek to tell him that something is definitely happening to Jackson. They believe that Jackson may be evolving into an alpha state, which has wings. 

 

Everyone agrees to meet in the warehouse district, and Scott and Isaac steal Jackson's body. When they're all in the warehouse, Gerard reveals that he's the kanima's master, and Jackson shifts so he can start attacking people. He shoves his claws into Derek's chest and throws him across the warehouse. Derek comes back for more, and Jackson swipes him across the middle paralyzing him. Gerard has the kanima take Allison by the throat so that he can make Scott help him with his plan. The kanima holds onto Allison until Scott helps Gerard give himself the Bite on Derek's teeth. When Gerard realizes that something's gone wrong, he tells the kanima to kill them all. Allison escapes, and then Stiles hits the kanima with his Jeep.

 

Lydia jumps out and runs up to the kanima, shouting Jackson's name. She holds up the key he gave her, and he starts to remember who he is. He shifts back to human. Derek and Peter take the opportunity to attack, and they both impale him on their claws. While he's dying, Jackson asks Lydia if she still loves him. She says she does. Jackson goes limp. Everyone cries, but then they notice Jackson's hands becoming claws. His eyes open, and they shine werewolf blue. Jackson rises up and roars at the sky. He shifts back to human again, shaking and looking terrified, and Lydia hugs him. 

 

Jackson's parents move him to London over the summer, after Derek has had a chance to teach him to control himself during the full moon.