"The Same Deep Water As You" is the first episode of the fourth season of One Tree Hill and the 68th produced episode of the series. It was broadcasted on September 27, 2006. In a shocking season opener, the aftermath of the post-wedding car accident unfolds. While Haley is deeply affected by Nathan's attempt to rescue Cooper and Rachel, Brooke confronts Lucas with her true feelings, and Peyton makes a startling discovery. Pressured by the fact that someone might know he killed his brother, Dan assaults Deb.
As Nathan shouts for help in a submerged car, after trying to rescue a drowning Rachel and Cooper, Haley stands on the bridge screaming for help. He lets go of Haley's bracelet and as it floats to the top of the water, Nathan can't hold his breath any longer and struggles to breath under the water. 29 minutes later, Lucas is in the hospital and as he walks down the corridor and sees Haley standing in her wedding dress. As he hugs her, she begins to cry. Before the accident, Haley and Nathan are talking about both Rachel's and Cooper's actions as they laugh about it. In the limousine that Rachel and Cooper are in, the situation is more intense. Rachel is in tears, begging for Cooper to like her, but he won't listen. He tells her that her and him never happened, but she says she needs to tell him something, that she's pregnant. Cooper insists he doesn't believe her so Rachel grabs the wheel to pull over. As the limousine skids, the car falls into the water and Nathan dives in after them. As he swims down and gets in the vehicle, he realizes he can't undo Cooper's seat belt. Eventually, he runs out of breath and screams for help. Lucas then drives past the bridge as a terrified Haley tells them what happened. Lucas jumps in after them as Karen checks Haley as rang 911. Lucas drags Cooper out of the water but finds the rest of the car empty. As he tells Haley, she panics screaming at him saying he is down there.
As he continues his search, he spots them at the edge of the river. With his arm collapsed over Rachel, Nathan lies still. Lucas warns Haley not to look, but it is too late. The emergency services arrive as Lucas and Haley run to their friends. Back in the hospital, Haley lies on Lucas' shoulder awaiting the news. Lucas says he should call Dan, who is washing a sign saying 'murderer' that is painted across his wall in red writing. As he does, he remembers shooting his brother Keith and then returns to look at the vandalized sign, just as his phone rings. After receiving no answer, Lucas hangs up as Karen meets him. She says she needs to talk about the pregnancy, as Lucas says how happy Keith would be for her, but Karen meant the other pregnancy test he found in a purse at the reception. Lucas says he doesn't know who is pregnant and Karen wants to know if history is repeating itself, just as they find out Nathan is awake. As they go to see Nathan, he thanks Lucas, but Lucas says he is the hero. As he does, Nathan remembers getting into the car and being unable to help and eventually ending up in a helpless situation himself. Meanwhile, Peyton is burning all her old pictures of Brooke, her and Lucas as she remembers a series of events leading through the love triangle she is involved in. She remembers the kiss in the library, confessing her feelings to Brooke, Brooke slapping her as she found out and also being told that their friendship is over and she never wants to speak again. With the final photo, of the three of them, Peyton rips out Brooke and burns the part of the photo, placing both her and Lucas together. She picks a record and as she pulls it out, she finds a piece of paper and gasps in shock in what was contained in one of Ellie's old record. Dan is cleaning his wall as the ghost of young Keith haunts him telling him someone else knows what he done. The ghost then appears at the window and watches a cop car arrive at his house, he tells him he is definitely not the only one. As Dan races to the window, he sees the car and Keith reappears at the sign on the wall saying that Dan's in trouble. The cops arrive and Dan shuts the blinds so they can't see the sign.
As the cops get to the door, Dan answers and is informed about his son's accident. Dan asks which one before arriving at the hospital to a frenzy of news reporters. Skills goes to see Lucas and is told about the kiss he told Brooke about. As they talk, Peyton arrives asking how everyone is. She hugs him as Brooke gets out of the elevator and is upset to see the two of them together. She walks off with neither of them seeing her. Brooke goes to see Rachel just as she wakes up. As the two seem to get along, Rachel asks about Cooper and tells Brooke about her being pregnant, and that she was lying about it. As she confesses, Lucas walks in. Outside, Brooke and Lucas are walking when he asks if she is pregnant as he found a test in her purse. Brooke assures him she isn't as he sighs with relief. Meanwhile, Dan is checking on Nathan and seeming the loving father. As Nathan and Haley go for tests, Dan asks to talk to Deb. As they are left alone, he begins to strangle her against the wall telling her to be afraid of what he is going to do to her. Nathan and Haley get back to their apartment where he surprises Haley with a revamped apartment and a picture of London Bridge. As he looks at a water lamp, he remembers being submerged under the car and screaming for Haley's help. She realizes what he is thinking and hugs him promising he is okay now. As she does, she tells him the thing she tried to in the car, that she was accepted into Stanford. Lucas goes to see Peyton and tells her about Brooke being annoyed at their kiss as it meant something to her. Peyton then finds out that Brooke hasn't said anything about her having feelings for him. She hands Lucas the note she found in Ellie's record and reveals that she might have a brother. Back in the hospital, Rachel goes to see an unconscious Cooper. She kisses him as a detective watches from behind. He asks her for a statement when she is feeling well enough, but begins pointing the finger as he finds it hard to believe a professional driver lost control whilst sitting next to him was a drunk highschool girl. He tells her to hope he wakes up to prove his theory wrong.
The river court is paid a visit by Lucas as they all ask about the people in the crash, Mouth especially interested in Rachel. Skills asks Lucas to talk to Whitey to get him on the Ravens team as he wants to go to college but doesn't have the money, he just wants a try out. Deb raids the kitchen for drugs and finds most of her pills empty as Dan paints his wall red due to the vandalism sign. He picks up a picture of him and Keith when they were kids and decides to visit Karen. On his arrival, Karen gives him no sympathy for not seeing Nathan. Dan asks Karen for coffee or a movie, but she refuses but Dan insists he wants to be there this time. Nathan's phone rings as he watches the news and ignores it. Haley answers and it is obviously a news reporter. She joins Nathan and they both can't believe how long the day has lasted. She asks Nathan to tell her what happened under the water, and as she asks, Nathan remembers going under the water and attempting to get Cooper's belt undone. As he tries, Cooper grabs his hand in the water. He looks up to find Cooper staring back at him, restraining him from undoing his belt. Nathan tells Haley he doesn't know what happened as Haley assures him it will be okay, as Nathan believes otherwise. In the hospital, Cooper flatlines as Rachel runs out the room leaving him alone. She watches him trying to be resuscitated as Nathan tells Haley he doesn't know if he done everything he could.
Cooper continues to be worked on in the hospital. As he is shocked, his heart begins to beat again. Rachel then sits with Cooper as he recovers. Haley visits him later to find Rachel who tries to ask how Nathan is, but Haley is furious with her after seeing her grab the wheel. She tells her to stay away from everyone. Lucas tells Karen that Brooke isn't pregnant but asks if she is happy with hers and she assures him she is. Lucas tells her he wants to study in Tree Hill to help her, but Karen insists he follows his dream to the further away college. Brooke brings Rachel some of her stuff back, and as she does, Rachel asks if she thinks people can change, which Brooke says they can’t. Eventually, Brooke gives Rachel her keys back, but she says to keep them and she can move in, if she wants. Surprised, Brooke gratefully accepts. Back at Lucas’, Peyton is there having a fun time as Peyton reveals she thinks about the shooting a lot wishing to take that day back for Karen, Keith, him and Brooke. They talk about her possible brother Derek, and she doesn’t know whether to ring him. As they talk, Brooke walks in and is shocked to find them together. She gets Peyton to leave so they can talk. She begins talking to Lucas and tells him that she feels as though she has been holding them together for him not her. She tells him she has stopped missing him and it shouldn’t be like that. She breaks up with him as Lucas has nothing to say except to apologize.
Mouth visits Rachel and finds her breaking out of hospital. Rachel is shocked to see him and confesses to everything she done. He tells her not to run away as people can change and it is time people decided to do it. Karen goes to see Lucas and is asked how she got over Dan when he didn’t love her back, but she says she will never know how she done it. As Haley sleeps, Nathan lies awake and remembers being underwater. He gets up and walks off as Haley lies awake too, scared for her husband. Peyton starts her webcam up again as Mouth finds Rachel’s bed alone. Instead, she goes to lie with Cooper. Brooke knocks for Haley and asks to talk to her. Karen goes to the hospital and is asked to take another pregnancy test to assure she is pregnant. Dan picks his gun up and aims it at the wall, as Deb puts a gun down and takes some pills with a glass of wine. A nurse returns to a room in the hospital and tells the patient she is definitely pregnant, Brooke sits shocked as Haley is too and she holds Brooke’s hand. Nathan stands at the scene of the accident staring out at the river, as Skills practices basketball. Peyton rings her brother and as he answers, she hangs up. As she walks around her room, Lucas stands in her doorway and hugs Peyton while the webcam videos them. As they do, an IM message appears from the screen name ‘WATCHMEWATCHU’ which she assumed was Ellie and welcomes Peyton back.
My name is Lucas Scott, I'm a senior at Tree Hill High School. Tree Hill is just a place somewhere in the world. maybe it's a lot like your world. maybe it's nothing like it. But if you look closer, you might see someone like you, or someone like my best friend Haley. If you're married in high school and not sure if your husband's okay, then i'd say you are a lot like Haley. Today was supposed to be the best day of her life. But it's amazing how things can change in the bling of an eye, or in this case in about 29 minutes.
- Lucas Scott beginning voice over