Alex's mom unplugs his flight simulator video game and reminds him that homework and chores come first.

Alex's father tells him he is not responsible enough for a dog, and Alex angrily says he hates him.

Jordan pins Alex against the bus window for the entire ride, crushing his birthday cupcakes.

Alex's teacher tells the class to pack up their belongings and leave school without giving any explanation.

The Man in the White Shirt flees the World Trade Center mall after a fireball erupts from the elevator.

Alex's mom sends the kids home from the hospital and warns them not to turn on the television.

The man sees flames pouring from the North Tower and watches a second plane deliberately crash into the South Tower.

Alex exits the homebound bus and the stray dog bounds onto him, knocking him to the ground and licking his face.

Alex joins older kids in a baseball game at the park and slides into home plate in a cloud of dirt.

Jordan throws a beer bottle from a bridge that strikes and injures the stray dog.

A veterinarian stitches up the dog, reads its microchip to reveal the name Radar and its address, and tells Alex about the terrorist attacks.

Alex stands on a bridge, sees smoke where the Twin Towers once stood, and resolves to return Radar as a sacrifice to bring his father home.

Alex meets Mac, and both share their fears about missing loved ones, realizing the men they are waiting for are strikingly similar.

Alex opens his front door and leaps into his father's arms.

Mac opens his front door and silently understands that his son Bobby will not be coming home.

On the eve of his 11th birthday, Alex Douglas quarrels with his father over a dog and says something he immediately regrets. The next morning, Alex's birthday goes wrong before it begins — a school bully destroys his cupcakes on the bus, and adults around him start acting strangely without explanation. While Alex and his sister Nunu are sent home from their mother's hospital and left in the dark, Alex's father survives the attack on the World Trade Center and begins a long, dangerous journey home. Alex bonds with a stray dog and stumbles through a frighteningly normal afternoon — a baseball game, a run-in with bullies — until a veterinarian finally tells him what has happened and he understands his father may be in danger. Desperate to make amends for his cruel words, Alex resolves to return the dog to its owner as a sacrifice, leading him to meet Mac, an elderly neighbor also waiting for a loved one. The day ends with a reunion that one family celebrates and another mourns in silence.

The headline events of September 11 through Alex's eyes.

Alex wakes on his birthday, rushes to the mirror to see if he looks older, and feels uneasy about his cruel words the night before.

Alex admires the Manhattan skyline from the school bus and thinks of his father driving a train toward the World Trade Center.

Alex spots a stray dog playing with a sock outside the bus window and whispers commands that the dog seems to follow.

The Man in the White Shirt is buying coffee in the mall beneath the World Trade Center when the entire building shakes violently.

Alex and Nunu enter an empty bakery and Alex leaves coins on the counter for two cupcakes after Nunu accuses him of stealing.

Alex lights birthday candles, makes a silent wish, and blows them out, leaving two trails of smoke rising in the air.

Alex's father is thrown to the ground when a massive chunk of metal crashes nearby and his cell phone skitters into the gutter.

Alex searches frantically for Nunu and finds her sitting calmly inside a large drainage pipe, playing a video game.

Alex's father and a policewoman link arms to form a cradle and carry an injured man to a medical tent.

Passengers covered in white dust and ash exit the ferry from Manhattan, and Alex invents a story about a giant exploding muffin to calm Nunu.

Mac's old friend Charlie calls from California to ask whether Bobby survived the attacks.

Pizza shop owner Mr. Patel invents a fake lunch rebate so that Alex and Nunu can eat without feeling they are accepting charity.

Alex and Mac take a model airplane into Mac's yard and fly it together, both briefly forgetting their fears.

Alex strokes Nunu's hair and sings 'You Are My Sunshine,' copying his father's bedtime routine until she falls asleep.

Alex's family visits Mac the next morning and Alex lights two candles on a slice of birthday cake to remind the grieving man to find the light.

September 11 begins like an ordinary birthday for Alex — his mom has made his favorite breakfast and a cake decorated with an airplane, and he boards the bus convinced the day will be great. As the morning unfolds, small moments of joy and strangeness pile up: Alex spots the stray dog from the bus window, Nunu goes missing at the park, and workers covered in ash begin arriving from Manhattan. Meanwhile, Alex's father endures physical and emotional shocks throughout his ordeal in the city, from being knocked off his feet by falling debris to breaking down in tears on a curb. Acts of quiet generosity by strangers — a pizza shop owner, a veterinarian, an old man with model planes — carry Alex and Nunu through the afternoon. By nightfall, Alex takes charge at home, cooking dinner and singing his sister to sleep, before his mother returns to find her son transformed.

The pivotal secondary moments that shaped the day.

Alex's mom shows him his birthday cake with an airplane design and reminds him that responsibility is the price of getting a dog.

The Man in the White Shirt learns from a security guard that a plane has struck the tower and runs toward the stairwell through smoke and debris.

Alex's mother tries to call Alex's father from the hospital and gets no answer.

Jordan and his sidekicks call Alex a 'raghead' and say he is 'one of them,' though Alex does not yet understand what they mean.

Radar growls at the bullies, lunges at Jordan, and chases all three boys out of the park before dropping a patch of Jordan's pants at Alex's feet.

Mac is introduced sitting alone in front of the television, desperately hoping his son Bobby who works in the North Tower will call.

After helping carry victims to safety, Alex's father sits on a curb, his hands trembling, and realizes what he needs is not rest but his family.

Alex's father enters a grocery store to use the telephone but cannot get a connection through to his home.

Alex's father walks out of his way to a hospital to donate blood but is turned away because so few people survived.

Alex watches news footage of the destroyed towers at Mac's house and confronts the real possibility that his father will not return.

Both Alex and Mac call their loved ones and hear nothing, while in the rubble of Manhattan a phone rings with no one there to answer it.

Alex and Nunu arrive at 417 Van Orton Street to find only the burned ruins of a house where Radar's owners once lived.

Radar scratches at the front door, Alex opens it, and the dog bolts into the night before Alex can stop him.

The Man in the White Shirt takes a shortcut through a park and spots a bandaged dog that bounds alongside him toward home.

Alex apologizes to his father for his hateful words, and the family realizes Radar had raced through the night to guide the man safely home.

The day's most significant turning points begin the night before, when Alex's father calmly refuses to promise a dog and Alex says something unforgivable, setting off a chain of guilt that drives the boy's decisions all day. When students are sent home and Alex's mother cannot reach her husband by phone, the weight of what is happening begins to press in, even as Alex remains shielded from the full truth. Alex's father, meanwhile, cycles through acts of heroism and moments of private collapse, including a failed attempt to donate blood and a breakdown on a city curb. The moment Alex finally sees news footage at Mac's house, reality becomes inescapable — and the parallel phone calls that go unanswered in both Mac's home and a pile of rubble sharpen the suspense unbearably. A series of small but decisive actions — Alex sending Radar into the night, the dog finding the man in a park, a knock on a front door — determine whose reunion will be joyful and whose will be silent. The story ends with Alex apologizing, a family restored, and one old man facing an empty doorway alone.