|“||You hated Kol!||”|
Throughout the seriesEdit
In Bringing Out The Dead, Kol was revived by Elijah after removing the white oak ash dagger. Kol mentioned to Klaus that it had been a long time since they last saw each other. Klaus appeared to be frightened of Kol and attempted to use the dagger against him, but was thwarted by Finn, who subsequently plunged the dagger into his hand. Klaus attempted to run, but was caught off guard by Rebekah, who stabbed him in the stomach with her dagger. Kol restrained Klaus with an arm lock.
After taking out their anger against their brother, Elijah, Rebekah, Finn and Kol informed their brother that they would leave him behind in Mystic Falls, and would be a family without him. Klaus threatened to hunt down each of them, but Elijah replied that Klaus would become the person he hated the most, Mikael. Kol, Rebekah, Finn, and Elijah are shocked by the sudden appearance of their mother Esther, whom they believed to be dead. Esther declared that she forgives Klaus and wishes for her and her children to be a family again.
In Dangerous Liaisons, their relationship is shown at the start of the episode when Kol defends Rebekah when Klaus is yelling at her for trying to kill Elena. Klaus threatens to put another dagger in Rebekah's heart, but it is clear, after Kol's comment, that they are all sick of the dagger threats. Klaus tells Kol he is in his house, to which Kol replies that maybe they should take it outside, with Esther interrupting their spat.
In All My Children, Kol was relaxing at the family's mansion with Klaus, who was sketching, when Rebekah arrived home, having been sleeping over at the Salvatore's, Kol immediately started teasing his little sister. Klaus found it amusing only to have Rebekah start to scorn him for his mocking while Kol took a seat, telling his siblings of his boredom and that he needed some sort of entertainment. He asked Klaus if he would go out for a drink with him, telling him it was the least he could do after daggering him. Klaus grudgingly complied, leaving with Kol. The two went to the
Mystic Grill, unaware that there was plan to dagger them now that they were all linked by their mother's spell. Caroline arrived and Kol immediately took interest in how attractive she was only to be thretaened by Klaus to not even think about it. Klaus left to pursue Caroline while Kol remained at the bar where he was daggered by Alaric Saltzman. Despite being linked and the other siblings being neutralized because of it, Klaus' hybrid side protected him from being neutralized but did give him pain. He realized it must be Kol and ran back to the grill, removing the dagger and saving him. Together, with thier older brother, Elijah, Klaus and Kol confronted their mother who was trying to perform a spell that would turn them human then kill them. With the help of the Salvatores, they stopped her plan and Kol left town, while Klaus stayed behind.
In Catch Me If You Can, Kol ruined Klaus' search for the cure by slaughtering the vampires he had been making in order to grow Jeremy Gilbert's Hunter's Mark. Klaus called up Kol, ordering him to leave Jeremy alone and threatening to dagger him if he did otherwise. Kol happily agreed but found a loophole in the agreement, compelling Damon to go after Jeremy for him. When Kol returned home he was confronted by Rebekah who pointed a dagger at him and Kol retaliated with the White Oak Stake only to be flung into a wall by Klaus before retreating. Klaus then tried to take Jeremy, telling him he was his best option of protection against Kol but Jeremy refused.
In A View To A Kill, when Kol discovered Elena and Jeremy's plan to kill him, he called Klaus in a rage, believing he was also a part of it. Klaus denied the accusations but Kol promised that when he was finished tearing apart the Gilberts, he was going to come for his brother. Kol was staked during the struggle with Elena and Jeremy and as he was set ablaze and fell to the floor dying, Klaus was standing in the doorway, witnessing his brother's death. However, because he had not been invited in, there was nothing he could do to try and help him or even comfort him. Kol's death sent Klaus into a state of fury, saying he would kill Jeremy and Elena for killing his little brother but when he unknowingly fell into a trap inside the house where Bonnie's magic contained him in a barrier. It would last for three days where he'd be stuck in the Gilbert home, Kol's scorched remains only feet away.
In Into the Wild, Klaus was still trapped by the magical barriers in the Gilbert home, forced to have to look at his little brother's burnt corpse. When Tyler and Caroline came to fix the damages done to the house from the fight with Kol, as well, Tyler's case, to gloat, Caroline started the clean up by laying some tarp over Kol's body, Klaus looking incredibly sad as she did so.
- Kol: "Long time, brother!"
- Klaus (To Rebekah): "Do you want another dagger in your heart?"
- Kol: "Again with the dagger threats? Don`t you have any other tricks?"
- Klaus: "Oh, go back to staring at yourself."
- Kol: "And who are you, my father?"
- Klaus: "No, Kol, but you`re in my house."
- Kol: "Then perhaps we should go outside."
- Kol: "I’m bored. Our sister is a strumpet, but at least she’s having fun. I need entertainment."
- Klaus: "What are you waiting for? Go on, have at it."
- Kol: "It’s not fun to go alone. Join me, Nik! It’s the least you can do after sticking a dagger in my heart."
- Klaus: "Okay. Why not? I didn’t have nearly enough to drink last night, what with you trying to murder Rebekah’s date."
- Klaus: "Say another word and I'll tear out your liver."
- Klaus: "Little brother. Just two days home and I am told you've already gone and made a mess."
- Kol: "Come on Nik, I was only having some fun."
- Kol: "I gave him a good and proper beating, just for old times sake."
- Klaus: "Yes, well you've had your fun. Now let him go and come home, avoid any more trouble or you will find yourself back in a box."
- Kol: "Hey, no need to be nasty about it."
- Klaus: "On the contrary, I find nastiness to be essential whenever my siblings try to sabotage me."
- The two share a reckless nature, having been responsible for the Originals' growing infamy in the early 1100s.
- Their relationship seems even a but more hostile than Elijah and Klaus'. However, despite bickering frequently, they have been shown to be on good terms, going out for drinks together and Kol doing Klaus a favor by keeping an eye on Jeremy in Denver.
- Kol seems to view Klaus as a monster, often comparing Rebekah's hostile actions to Klaus', such as when she took a group of Mystic Falls vampires hostage at the school and especially when she was prepared to dagger him like Klaus had, scolding her by telling her she's "no better than Niklaus". This seems to stem from what his family has been through and knowing Klaus caused a lot of it. He even described Klaus' actions in the past as "horrors" to Elena.
- Like Rebekah, Kol generally refers to Klaus as "Nik", with Klaus having gone by that name in the early 20th century, a time when he was living with Rebekah and Kol.