As they leave their house to walk to school, they see a car approaching, with the new owners of the house next door. (The daughter, Celia, expresses that she hopes they will let them swim in the pool at this home). There is a moving van and a luxury sedan, and in the car is an African American man with a much younger attractive woman, and they pique Abel's interest. He watches them tour the grounds, and sees a younger Caucasian man seeing to the unloading of items from the moving van. Abel does not acknowledge when this man waves to him. Abel assumes the older man and younger woman are married, and the younger Caucasian man is a mover, and he is upset when he sees the young man kiss the woman when the older African American man has his back turned. It turns out that the new homeowners are a married biracial couple, Chris and Lisa Mattson (Patrick Wilson and Kerry Washington), and the older African American man is Lisa's father (Ron Glass) They are new homeowners, and quite engagingly excited and in love. Abel is a cop; he is seen shaking down an informer in a parking lot. The informer comments on a shift in Abel's attitude and behavior recently; a hostility and new edge to him.
Chris readies to leave for work in the morning, and there is a parking ticket on his windshield, because his fender exceeds the line of the curb; it is a warning, and is signed "AT," for Abel Turner. He is miffed; Lisa says he should not make much of it. Chris returns after work and enjoys a cigarette in his car, while listening to rap or hip-hop music. Abel appears suddenly, motioning Chris to roll down his window. He then frightens Chris, and jokes that no matter the neighborhood, it is dangerous to lower the window even when motioned to do so by a stranger outside. He chides Chris for smoking, even though it is not illegal ("Not yet," Abel says), and jokes that even he listens to hip-hop all night, "when you wake up in the morning, you'll still be white."
The next day, Chris and Lisa have sex in their swimming pool at night. Abel's children are watching. Abel arrives home to see this spectacle, and is upset. He has home security floodlights, and they shine into Chris and Lisa's window, keeping them awake and irritating them, clearly meant to be payback for their carelessness. He leaves them on every night, and Chris resolves to discuss with Abel.
When Chris has the opportunity to discuss, at the end of a jog one morning, Abel claims that it is to prevent crime, and Chris does not get what he needs. Chris helps Abel while he works under the hood of his car, and it results in a finger injury when the hood moves suddenly. It is uncertain whether Abel is intentionally antagonizing Chris or not.
Abel's children play in their yard, and a ball goes into Chris and Lisa's yard. Lisa works from home, and when they come over to retrieve their ball, Lisa strikes up a friendship with the kids, and asks them to bring their father over for a housewarming party they are having.
The flood light problems continue. Lisa says she will talk to Abel. She thinks she understands this African American man, and that Chris has issues, that they may even be related to his difficulties with Lisa's father, and a tendency to project this onto Abel. Chris goes to Abel's house instead though, to ask him to keep his flood lights off, and Abel says he had meant to do so, but has been busy; he claims it involves doing recircuitry of the whole house. Abel takes Chris on his "neighborhood rounds," where he checks on the safety of the neighborhood. He at long last confronts Chris over his lovemaking being visible to his children, and asks Chris that he considers if his lifestyle and behavior are appropriate to this neighborhood, implying that he wants them to move away.
Chris and Lisa have dinner with Lisa's father, who tells them they could choose to move away, if they wish, because acrimony with an LA police officer may mean trouble for them. Chris tells Lisa's father that he does not discuss issues with Chris, and acts as if Chris is not there, and does not like him. Lisa's father then pointedly says that he wonders if the young couple will have children, and if they do, whether Chris will know how to protect them.
Abel arrives to the housewarming party by himself. He is garrulous but has an edge, and criticizes Chris and his friends for their liberal tendencies, on things from the environment to police brutality. As he leaves, Chris tells Abel that he is taking offense to him, but does not plan to move.
One evening, they hear noises downstairs, and find the tires of Chris' car slashed. They suspect Abel. They call the police to come, and the police do little.
Abel and his partner burst in on a domestic incident, and Abel chases the armed African American perpetrator into an alley by himself. He disarms the man effectively, but then lectures and beats the man for not taking care of his family.
When he returns home, he sees his children off. They are to spend time with an aunt.
Chris now buys his own floodlights, and shines them into Abel's bedroom, as a way of taking matters into his own hands.
Lisa soon reveals that she is pregnant. This brings a rift into their marriage. Chris does not want to have children yet. Lisa skipped birth control pills to force the issue; she thinks Chris is being shortsighted, and chooses to force the issue. He leaves for work angry.
Abel is confronted at work by the Internal Affairs Department, for his over-board treatment of the domestic incident perpetrator, and told to go out on leave. Abel sees his police co-workers outside, discussing a bachelor party for one of them that evening. Abel tells them to have it at his house, since his children are away.
The bachelor party is very rowdy. There is loud music, alcohol and strippers, and many partying cops. It is keeping Lisa and Chris up all night, and Chris goes over to tell them to stop. They harass him mildly, try to give him drinks, but then pin him, and have a stripper simulate fallacio He leaves humiliated.
Chris goes to a local bar, and as he finishes his drink, Abel enters, and buys Chris a drink. He tells Chris that he lost his own wife, when a car hit her on a highway, and she was seen as a low priority at the treating Emergency Room. Chris expresses cursory sympathy, says Abel cannot know whether this was true at the emergency room, and leaves. Abel makes a last cryptic comment about his wife, wondering what she was doing out in that area, at that time, when she was supposed to be working (implying she may have been unfaithful to him).
Abel leaves a video of Chris with the stripper in their mailbox the next day for Lisa to see, and she angrily looks Abel's way, knowing it is his doing.
Wildfires rage in the hills surrounding the community. The neighbors are holed up in a home down the hill, waiting to see how fire officials will instruct them. Lisa goes home, and Abel's informant is there, trashing the home. It is at Abel's direction. Lisa surprises him, and it leads to her falling, and the possibility of harm to the pregnancy. Chris races home when he hears his burglar alarm go off. A frustrated Abel goes with him, realizing that the criminal he sent did not leave undetected. Chris rushes to the injured Lisa, and Abel comes upon the criminal, who stands helplessly as Abel shoots him three times in the chest.
Lisa is in the hospital. She is uninjured, and the pregnancy is alright. Chris and Lisa return home. The wildfires are not contained and they are instructed to pack a few things and leave their home. Abel watches from his home nearby. He is hosing off his roof, and does not want to leave. Chris thanks Abel for helping him, tries to express a sense of community with Abel. When Chris and Lisa finally leave, Abel enters their home, hoping to retrieve the criminal's cell phone, where he is afraid his call to the perpetrator can be traced, implicating him in the break-in and murder. He does not find it, and Lisa and Chris unexpectedly return. Chris discovers the cell phone ringing in a bag under their bed, and picks it up. He dials the last number logged on the phone, and Abel picks up his phone, Chris hearing his voice, and realizing Abel is responsible for the break-in. Abel tries to convince him that the perpetrator was a police enemy, and was trying to set Abel up, but Chris throws the gun to Lisa, and tells her to race away and get the phone to the police. Abel shoots a hole in Lisa's car, and Chris tries to beat him, eventually leading to a standoff with Chris holding Abel's dropped gun, Abel now holding a second gun that he keeps in leg holster. The police arrive, and Abel tries to convince them to shoot Chris, but Chris finally throws Abel off, by asking if his distractions are related to his wife's death, and how he was not able to recognize that she had become unfaithful to him. Abel fires on Chris, but is killed by the police in the standoff.
Chris is in the ambulance, and has a gunshot wound to the chest, but he is OK. He and Lisa talk about their pride in their home, neighborhood, soon to be family.