A Muslim-American soldier Salam Abdullah sacrifices himself by jumping in front of his best friend Anthony Lockheart during a suicide attack in Afghanistan. Back home in Pennsylvania, Anthony's sister Monica is pulled from her high school class, leaving her Middle-Eastern American boyfriend Ibrahim Airtibak worried. The news devastates Salam's parents, Suliman and Alina, while Anthony's parents, Joseph and Linda, and his sister are left confused by sensationalist news stories falsely claiming Salam may have helped orchestrate the attack himself. While Anthony wakes up to find his best friend dead and leg gone, a young white nationalist Ricky Tully bullies Ibrahim while the rest of the kids stay idle or join in, leaving Ibrahim isolated. Ricky also sends Monica white-nationalist articles and videos. Showing signs of severe PTSD and prescriptions of anti-depressants in hand, Anthony is discharged and sent home due to overcrowding in the hospital. At the Westchester Mosque, Suliman discusses with the other community leaders publicly condemning terrorism in a news conference, to which everyone reluctantly agrees.
One week later, Monica meets with Ibrahim to break up with him and says she has been seeing a lot of "facts" about Muslims that she doesn't like. Ibrahim reminds her that he's not Muslim, but she tells him it's not about that and leaves with Ricky. On the ride home, Monica refuses an aggressive sexual advance from Ricky, who threatens to tell her parents that she and Ibrahim had sex. She appeases him enough to leave the car, where she finds her brother in the living room and gives him a long sobbing hug. Anthony calls Suliman, who is readying his speech for the press conference, and tells him that he will attend. After his speech, Suliman is asked by a TV Personality about possible terrorist ties his son had, so Anthony causes a stir by climbing on stage and shames the reporter on national television for trying to spread lies.
The morning of Salam's funeral, Anthony wakes up to a text message from his sister among empty whiskey bottles, medication that reads "DO NOT consume with Alcohol", and a pistol. At the high school parking lot, Ibrahim gets punched by Ricky, but doesn't fight back because he knows Ricky is trying to trap him into getting in trouble. At the funeral, Joseph, Linda and Monica are taken aback when Alina sits in the back and Suliman mutters the words "Allahu Akbar" (God is Great), a phrase they associate with terrorism. Ibrahim, injured, embarrassed and ashamed, goes through sobbing spells and numbly searches the web when he finds and messages a suspicious social media profile addressing anti-Muslim bullying. Over the next four months, Anthony falls deeper into depression and addiction, Suliman and Alina struggle to cope with their sons death, Joseph cheers and Linda is saddened by Trump's presidential victory, Monica starts a sexual relationship with Ricky while falling deeper into (real) white-nationalist propaganda, and Ibrahim's new online friend sends him gifts and (real) radical Islamic-terrorist propaganda articles and videos.
At a PTSD support group, Anthony is enraged by the anti-Muslim sentiments shared by one of the group members and discusses discrimination with an older black veteran. Meanwhile, Ibrahim shares his desire to convert to Islam with his mother Hasna, who is surprised with his new radical views, and she suggests that they attend the local mosque together. When they do, Hasna cries as she tells the Imam and Suliman that Ibrahim is getting bullied and Suliman agrees to mentor Ibrahim after he has dinner with Anthony. While at dinner, Anthony stands up to a racist man who verbally attacks them. At home, after seeing first hand the discrimination Suliman and Alina face daily, Anthony confronts his family about their prejudiced views, which culminates in his attempted suicide. Concurrently, Suliman meets with Ibrahim, who scares him with his radical views. Joseph, shaken by Anthony's attempted suicide, goes to the Abdhullah home and tearfully makes amends with Suliman and Alina, while Linda and Monica react by falling deeper into anti-Muslim media. The next day, Ibrahim finds his car keyed with the word "Terrorist" and smashed with rocks, his mother attacked and her shop vandalized. In the hospital, Suliman visits Anthony, who is hopped up on prescription drugs and gets pulled kicking and screaming out of the room. Once home, Ibrahim tells his online mentor about the vandalism and his mothers attack, who replies by saying that their group can help him get revenge and send him money. Ibrahim agrees.
A month later, Anthony is released from the hospital while Ibrahim drives to a local gun show. When Anthony calls Suliman to tell him he would like to visit, Suliman accidentally does not end the call and Anthony overhears a conversation in Arabic between Suliman and the Imam about how Suliman is concerned about Ibrahim. Anthony only recognizes the words "Ibrahim", "Jihad" (holy war), "qutil" (kill), and "kuffar" (infedels). At the gun show, Ibrahim purchases an AR-15. When Anthony visits Suliman and Alina, he sees the death threats that have been sent to Suliman, as well as literature on "child soldiers". He then follows Suliman to Ibrahim's home and witnesses Suliman yelling at Ibrahim and Hasna. After Suliman leaves, Anthony speaks to Ibrahim, who lies to him that Suliman is trying to recruit him to a terrorist group.
Anthony confronts Suliman the next day, but slips and falls as Suliman leaves to follow Ibrahim to school. Anthony calls the police on his longtime friend. When Suliman arrives at the school, he tries to stop Ibrahim from entering the school with his rifle, but is intercepted by a police officer. Suliman is able to get away from the officer when they hear gunshots erupt from the school. He finds Ibrahim and talks him down, but a loud helicopter startles Ibrahim and he accidentally shoots Suliman in the chest. At the hospital, Anthony apologizes to Suliman for not trusting him and Suliman tells him to pray for the world to heal and dies. At the funeral, Anthony's family consoles a broken Alina while Anthony leaves his bronze star on Suliman's grave.