The film begins bright and early on September 11, 2001, showcasing the hijackers engaged in prayer within their hotel room before they set off for Newark Liberty International Airport. Upon arrival, the passengers and crew board United Airlines Flight 93, unwittingly accompanied by the hijackers. As the flight prepares for takeoff, it encounters heavy rush hour traffic, causing a short delay while the other three planned hijackings successfully take off without incident.

After a brief hold-up, Flight 93 finally launches into the sky and passes over Manhattan. The hijacker, Ziad Jarrah, catches one last view of the iconic World Trade Center before they ascend. Meanwhile, air traffic controllers are closely monitoring the flights and soon notice American Airlines Flight 11 veering toward New York City. In a shocking turn of events, Flight 11 descends into Lower Manhattan and collides directly with the North Tower of the World Trade Center. At this moment, the air traffic controllers remain unaware of the catastrophic crash. CNN broadcasts the first international imagery of the smoking tower, prompting alarmed reactions as transmissions relay the gravity of the situation.

As confusion ensues among the traffic controllers trying to decode the unfolding chaos, they witness United Airlines Flight 175 also descending and heading towards NYC. It is only until now that they comprehend the severity of the hijacking incidents. Shortly thereafter, American Airlines Flight 77 undergoes a similar hijacking. The urgency heightens as controllers inform the U.S. Air Force, who contemplate the extreme measure of shooting down the suspected hijacked planes. The situation escalates as they watch in horror when Flight 175 crashes into the South Tower, broadcast live on television.

Amidst the turmoil, news of the World Trade Center attacks reaches Flight 93, prompting the hijackers to initiate their own assault on the aircraft. In a calculated move, one hijacker constructs a fake bomb using clay and plastic, while the others breach the cockpit. They strategically place a photo of the U.S. Capitol—targeting their attack—onto the flight yoke mount clip. At this point, Flight 77 has also crashed, igniting a massive fireball at the Pentagon.

Despite their efforts, Ben Sliney and his team face significant challenges in coordinating a response with the Air Force due to a lack of armed planes available. In a decisive moment, Sliney orders the grounding of all flights across U.S. airspace.

Meanwhile, the hijackers do not restrict the passengers from making phone calls through the on-board GTE Airfone system. Upon receiving alarming news about the attacks on the WTC and Pentagon from their loved ones, the passengers realize their grim reality: inaction equals certain death. United in their resolve, they decide to storm the cockpit and take back control of the aircraft. In a poignant farewell, they make one final set of phone calls to friends and family, articulating their courageous intentions. The crew members improvise weaponry using items like cutlery, wine bottles, and fire extinguishers.

Amidst this chaos, they learn that one courageously determined passenger has some flight experience, even if limited to non-commercial flights. With hope resting on him, they begin strategizing their counterattack against the armed hijackers. Suspecting the bomb may be a facade, they launch their offensive, first overpowering the hijacker with the supposed bomb using a fire extinguisher. Witnessing their comrade’s defeat, the terrorist in the cockpit tries to signal his fellow hijackers, resorting to desperate measures to fend off the passengers’ advances, but ultimately meets a similar fate.

Despite Ziad Jarrah’s intense maneuvers to destabilize the attackers, the courageous passengers endure and make their way into the cockpit. Through tremendous struggle, they engage in a desperate fight for control as the plane begins a perilous nosedive toward the ground. The film culminates tragically as Flight 93 crashes into an open field, leaving an indelible mark on history.