"How Can You Be Sure?" is the nineteenth episode of the first season of One Tree Hill and the 19th produced episode of the series. It was broadcast on April 20, 2004. History seems to be repeating in Tree Hill as Lucas learns that Brooke may be pregnant and makes a decision regarding their future, while Brooke continues to give him the cold shoulder about the situation. Haley considers sleeping with Nathan and Karen gives Keith an answer.


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Brooke tells Lucas her test is positive.

After being told she might be pregnant with his child, Lucas is shocked with what Brooke has just told him. He arranges to go to the drug store together to get a pregnancy test together as he wants to support her with his possible child. Keith is standing at Karen's door proposing to her, but Karen has seen a new prespective of life when she went to Italy and says no to Keith's proposal as she thinks there is more out there for her. At Brooke's house, Lucas is waiting for her to come out the bathroom with the pregnancy test. As she comes out, she reveals a positive test and although Brooke is hesitant to it, Lucas offers his help and support. Haley and Nathan are in his new bedroom, as Haley leans over to switch off the alarm clock, Nathan notices Haley's tattoo she has got of his jersey number, he is thrown into a state of shock.

The next day, Lucas and Brooke go to the women's clinic. Brooke is still hesitant of trusting Lucas and is not happy to recieve support. As they leave the clinic, Dan drives by and is curious to see Lucas leaving with Brooke. At highschool, Lucas is mad at Nathan, due to him seeing Nathan and Peyton kissing the night before. When he comfronts Nathan about it, Nathan laughs about the kiss saying it was the compulsory midnight kiss for the boytoy auction, believing him, Lucas leaves. Nicki knocks at Jake's door and on opening, she barges into the house to see her daughter. Peyton is holding Jenny and takes her in the other room as Nicki tries to get Jake to forgive her. While in Jake's house, she picks up a photo of the Raven's team and realizes Jake and Lucas are on the same team.

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Nathan confronts Haley about her tattoo.

Brooke has still not heard from her doctor, and as Lucas waits anxiously, they begin arguing with each other. Brooke calls Lucas 'Danny Junior' knowing it will work him up, whereas Lucas responds saying he doesn't even know if the child is his considering the amount of people she has slept with. Just as he says this, Brooke's cell rings and she finds out it is the doctor. Ending the call, she confirms to Lucas that she is pregnant and storms away from Lucas. Dan visits Deb and finds out that she has been providing Nathan with food and money. Dan is furious and says that if she wants Nathan back, then she will have to stop it and let him learn from his mistakes. He continues to tell Deb about Lucas and Brooke leaving the clinic, aware that she will go to Karen to tell her about her son. Nathan and Haley get back from school, but Nathan shows no interest in making out and Haley begins questioning him why. He tells her he knows about the tattoo and doesn't understand that she will get something as permanent as a tattoo yet won't have sex with him.

The next day at highschool, Peyton and Lucas begin talking after Brooke walks away from Lucas. He tells her that something bad has happened between him and Brooke, but Peyton just jokes about the idea without knowing the actual extremity of the issue. Lucas then asks her what they were thinking, all three of them, by getting involved in the situation which he now regrets. Haley takes Peyton to one side and asks advice about Nathan. She confides in Peyton telling her about her worries of Nathan looking elsewhere because she is not willing to give up sex until marriage. Peyton thinks maybe Nathan is the right guy, but Haley is sure he is as she is completly in love with him. Peyon tells her that if she loves him, she has gone further than her and Nathan ever went. Dan visits Lucas while in training, he tells Lucas he knows about the pregnancy and thinks he should get an abortion for Brooke. Lucas realizes that he wanted to abort him when Karen fell pregnant and walks out on Dan. Keith and Deb are at the cafe, where he tells her about the proposal and about him being rejected. Deb apologizes for him but says Karen does still need him, but Keith believes she might need him, just doesn't want him. Dan visits Nathan telling him he isn't ready to own his own apartment as there is so much stuff to worry about, including mortgages and household bills, Nathan argues back telling him that he will just get a job to support his bills.

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Nicki and Peyton insult each other.

Nicki goes to see Peyton at the school and tells her that Peyton is just a temporary babysitter, and that she isn't going to be needed anymore as her mother is back. Peyton argues back saying Nicki is the one that isn't needed. As Nicki leaves insulted, Brooke asks Peyton who she is and Peyton is shocked that she is being talked to by Brooke. She asks what is the matter as Lucas was really upset before, causing Brooke to realize she is making a mistake and tells her that she doesn't want to talk anymore. Lucas goes to see Jake and tells him about Brooke. Jake tells him that his life will change with a baby and Lucas believes he isn't ready for a baby. Haley walks in on Nathan selling his car. He says that he needs to make some cut back and Haley offers some support, but Nathan refuses. Nathan is now at the point where the two can't kiss as Nathan is determined not to pressure Haley into sex, where he is doing the opposite. It's the following morning, and Lucas can't sleep, he gets up to find Karen in the kitchen too. He
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Lucas is slapped by Karen.

tells her about Brooke and warns her before hand it is going to hurt her. Once he tells her, Karen slaps him and then apologizes because of it. Lucas believes he deserves it but Karen starts crying saying it is exactly what she didn't want for Lucas, the two of them are both too young. Lucas asks Karen how close he was to not existing, but Karen says Dan wanted an abortion, she realized she wanted to keep him. Lucas begins to cry and tells his mom he doesn't know what to do.

Haley is with Lucas the next day at the cafe. She tells him she is thinking about having sex with Nathan, but Lucas advises against it, saying he regrets having sex and losing his virginity. Nathan returns to Debs house and she offers him to stay with her. Nathan still says no and Deb says how she wishes she could change what happened in the past. Nathan asks Deb why she cheated with Dan, but it is because the two of them grew apart and they got together so young. She then tells him it was not right as she had a commitment to Dan and Nathan and definatley wasn't worth it. Nicki is waiting on Lucas' doorstep. She tells Lucas about who she is, Jenny's mother, and asks for him to keep them two having sex quiet. Lucas agrees as he does not want to tell Jake. Keith goes to see Lucas and is told that Lucas can probably play by the playoffs. He asks Keith why he stood by his mom when Dan left her. Keith tells him it was because it was the right thing to do. He tells him that Lucas was the best thing that ever happened to Karen. After apologizing for his behavior when his mom was away, Keith tells him how proud he is of Lucas, and that he will always be there, no matter if he is not around as much as usual.

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Brooke tells Lucas she lied about her pregnancy.

Haley is still concerned about Nathan as he still won't kiss her. Asking why, Nathan tells her that it is because he tends to drive people away from him and really doesn't want to do that to her or pressure her into sex. Nathan then tells her he loves her and Haley, in shock, replies to tell him she loves him too. Lucas and Dan meet and Lucas thanks him for sharing his views as he now knows to do the opposite. Dan tells him that everyone makes mistakes and they have to learn to live with it, like he did with his mistakes, making Karen pregnant. Keith goes to see Karen and tells her that Tree Hill is no longer his home and he has decided that he is going to leave Tree Hill. Lucas goes to see Brooke and tells her that Dan didn't want him but no matter what she decides, he is not going to be like his father and will stand by Brooke and her decisions. Brooke starts crying with Lucas' decision. She tells him she has lied all along and makes Lucas furious and they begin arguing. She tells him the doctor called to tell her when Lucas had just called her a slut. Lucas can't believe she did this to punish him but it is because she is still hurt over Peyton and him. Lucas says she never meant to hurt her, but Brooke said it did anyway.

Dan is looking through a box of all of Nathan's history. As he gets to the bottom of the box, there is a lot of stuff relating to Lucas' life showing how much he cared about him. Peyton is with Jake as Nicki waits outside for her daughter. Keith goes to a pawn shop to sell his ring as Lucas goes home to tell Karen the news. He starts crying and thanks her for everything she has done for him.

Memorable Quotes

"I told them the sorry bro-ho kicked me to the curb"
- Brooke Davis to Lucas Scott about what she told the doctor about the father of their child

"Better be careful Danny Junior, You never know how many kids you'll end up with"
"Oh that's real nice Brooke, and by the way, it's not like I'm the only guy you ever slept with"
"What's your point?"
"How do I even know it's mine"
- Brooke Davis and Lucas Scott about Brooke's pregnancy

"What? Worse than the death-wish-best-friend-love-triangle? What did you do? Tell her she was fat?"
- Peyton Sawyer to Lucas Scott after finding out something has happened between him and Brooke Davis

"Maybe you're just not sure if Nathan's the right guy"
"No, I'm, I can safely rule that out, I can't breath when I'm around him and when I'm not around him I wanna be, I'm totally in love with him"
"Then you've gone further with him then I ever did"
- Peyton Sawyer and Haley James about her having sex with Nathan Scott

"So your advice is to get an abortion, the way you would have aborted me?"
- Lucas Scott to Dan Scott

"All the eyeliner in the world won't make you anything more than a psycho stalker bitch"
- Peyton Sawyer to Nicki

"If you need some extra money, I could always be your suga momma"
- Haley James to Nathan Scott

"This is gonna hurt you Mom, and I'm sorry"
"What happened?"
"Brooke's pregnant"
- Lucas Scott and Karen Roe

"How close was I to not existing? Dan wanted to have an abortion Mom, why didn't you listen to him?"
"Because I realized, I wanted you in my future"
- Lucas Scott and Karen Roe

"When my mom got pregnant, and Dan left, why didn't you? Why did you stand by her?"
"Well it was the right thing to do, and I love her, and I wanted to protect her, but she really didn't need it"
- Lucas Scott and Keith Scott

"I love you Haley, and it scares me a little bit, but there it is"
"Wow, there it is...I love you too"
- Nathan Scott and Haley James

"This whole thing scares the hell out of me ok? But whatever you decide to do, I'll be there and if you're not ready, then you're not ready, but if you want to have this baby, then so do I"
- Lucas Scott to Brooke Davis

"I lied"
"I'm not pregnant"
- Brooke Davis and Lucas Scott

"Brooke, I never meant to hurt you"
"That doesn't really matter Lucas, cause in the end it hurts all the same"
- Lucas Scott and Brooke Davis about him having an affair with Peyton


No Voiceover


  • "Someone Like You" - Master Source
  • "Coming Undone" - Highwater Rising
  • "Spitting Games" - Snow Patrol
  • "Wrecking Ball" - Viva Voca
  • "Broken" - Hathaway
  • "Heaven" - The Fire Theft
  • "Love In December" - Club 8
  • "Everybody Hurts" - R.E.M.

This episode's title originated from the song How Can You Be Sure?, originally sung by Radiohead.


  • Whitey does not appear in this episode.
  • Nathan's nipple ring makes a reappearance which was last seen in the Pilot episode.

Episode References

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