Lakeview Terrace

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Abel Turner (Samuel L. Jackson) is a twenty-eight-year veteran of the LAPD. A single and widowed father, he is particularly strict with his two children, Marcus (Jaishon Fisher) and Celia (Regine Nehy). As his kids leave for school, the new neighbors begin moving in next door. They are a young interracial couple, Chris and Lisa Mattson (Patrick Wilson and Kerry Washington), who are recently married and buying their first home.
Chrisâs first exchanges with Abel have somewhat hostile undertones, with Abel making comments about Chrisâ smoking (which Chris hides from Lisa) and listening to hip hop music. The following night, Chris and Lisa have sex in their swimming pool. Unknown to them, Abel's children are watching. Abel arrives home to see this spectacle and is upset, so he repositions the home security floodlights so they shine into Chris and Lisa's window, keeping them awake. When Chris confronts him, Abel claims that the lights are part of his security system to prevent crime and says that it is a complex process to shut down the system and the lights.
Abel attends a housewarming party hosted by Chris and Lisa. He is garrulous but has an edge, and criticizes Chris and his friends for their liberal political and social tendencies. He also exposes Chris' smoking to Lisa, as Chris has been discarding his cigarette butts on Abel's lawn. As he leaves, Chris tells Abel that he is starting to take 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 and call the police. However, because of Abel's status within the LAPD, the arriving officers are unable to do anything.
Chris and Lisa have dinner with her father, who warns them that acrimony with a police officer may cause trouble. Chris buys his own floodlights and shines them into Abel's bedroom. Lisa later reveals that she is pregnant, which causes conflict as Chris does not yet want to have children. Chris later finds out that Lisa skipped birth control pills to force the issue, and when he confronts her she accuses him of being shortsighted. Meanwhile, Abel is suspended without pay for his abuse of a suspect on the job, which brings even more fury out on him. He hosts a loud bachelor party while the kids are away with their aunt. Chris arrives to complain about the music, but Abel taunts him.
Chris plants trees at the fence between their houses, which leads to an almost violent exchange between the two neighbors, as Abel refuses to have their trees hanging over his property without permission. Later Chris goes to a local bar, and as he finishes his drink, Abel enters and tells Chris that he lost his own wife, when a car hit her on a highway. Abel makes a last cryptic comment about his wife, wondering what she was doing out in that area, at that time with her white boss, when she was supposed to be working, implying she was being unfaithful to Abel.
Both Abel and the Mattsons attend a barbecue in a home down the hill. Abel's informant Clarence Darlington (Keith Loneker) is sent to trash their home, as another means of making the Mattsons uncomfortable in the neighborhood. Lisa goes home early, surprising Clarence. They struggle, which leads to Lisa being knocked out; but not before she triggers the alarm. Chris races home upon hearing the alarm, followed by a frustrated Abel. Chris rushes to the injured Lisa, while Abel comes upon his hired criminal trying to escape and shoots him dead in the pool. The Mattsons go to the hospital, where Lisa is found to be okay.
Wildfires are raging in the hills surrounding the community and the residents of the neighborhood are instructed to pack their things and leave their homes. Abel remains at his house, hosing off his roof, as he does not want to leave his home. With the Mattsons at the hospital, Abel enters their home, hoping to retrieve a cell phone which Clarence left behind, as he is afraid his call to the perpetrator could be traced, implicating him in the break-in. Before he can find it, Lisa and Chris unexpectedly return from the hospital and Abel returns to his home. Chris thanks Abel for helping him during the break-in, trying to express a sense of community with Abel. While the Mattsons are packing to leave, Chris discovers the cell phone under their bed and picks it up. He dials the last number logged on the phone and hears Abel answer. Chris realizes Abel is responsible for the break-in, and Abel realizes Chris has discovered the phone.
Abel comes over with his gun drawn, trying to convince Chris that the perpetrator was trying to set him up. He and Chris struggle and Chris tells Lisa to take the car and the cell phone to the police. Abel shoots Lisa's car and she crashes into a parked car. Chris tackles Abel and gets his gun. After pistol whipping Abel and seemingly knocking him out, Chris runs to help Lisa out of the car. This leads to a standoff, with Chris securing Abel's 9mm semi-automatic handgun and Abel drawing his backup revolver from his ankle holster.
Deputies from the LA County Sheriff's Department arrive. Abel hides his gun behind his back and tries to convince them Chris is unbalanced due to the break-in and attack on Lisa earlier that day. Chris refuses to drop his weapon until Abel puts his down, but Abel raises his arms and insists that he is unarmed. Chris finally throws Abel off, by asking about his wife's death and how he was unable to recognize that she had become unfaithful to him. Infuriated, Abel shoots Chris and is promptly gunned down and killed by the deputies. Chris is taken to an ambulance with a gunshot wound to the chest, but is told he will live. He and Lisa later talk about their pride in their home, neighborhood, and soon-to-be family.

Question: Who is Abel's informant?
Answer: Clarence Darlington