Plot Summary
Zero Day is a six-part political thriller series that premiered on Netflix on February 20, 2025. Created by Eric Newman, Noah Oppenheim, and Michael Schmidt, the series is directed by Lesli Linka Glatter and features an ensemble cast led by Robert De Niro.
The narrative centers on George Mullen (Robert De Niro), a former U.S. President who is called out of retirement to lead an investigation into a catastrophic cyberattack that devastates the nation, resulting in widespread chaos and significant loss of life. As Mullen delves deeper into the origins of the attack, he confronts a complex web of political intrigue, personal betrayal, and challenges to his own mental acuity.
Mullen uncovers a conspiracy involving high-ranking officials, including his own daughter, Congresswoman Alexandra Mullen (Lizzy Caplan), and House Speaker Richard Dreyer (Matthew Modine). Their misguided intent was to unite the country by orchestrating the attack, hoping to prompt decisive governmental action with financial backing from billionaire Robert Lyndon and tech mogul Monica Kidder .
Key Characters:
Evelyn Mitchell (Angela Bassett): The incumbent President who appoints Mullen to lead the investigation.
George Mullen (Robert De Niro): The former President tasked with uncovering the perpetrators behind the cyberattack.
Alexandra Mullen (Lizzy Caplan): Mullen’s estranged daughter and a Congresswoman, whose involvement in the conspiracy adds a personal dimension to the crisis.
Richard Dreyer (Matthew Modine): The Speaker of the House, revealed to be a central figure in orchestrating the attack to consolidate political power.
The Nature of the Cyberattack
The attack is a large-scale, multi-layered operation targeting the United States’ essential services, including:
- Power Grid Failures – Widespread blackouts disrupt cities, causing chaos.
- Banking System Disruptions – Financial institutions experience system crashes, leading to panic.
- Media and Misinformation Manipulation – Social media and news networks are hijacked to spread misinformation and exacerbate public distrust.
- Government Infrastructure Breach – Sensitive data leaks and key government agencies face internal security compromises.
This cyberattack is carefully coordinated to create confusion, fear, and instability, making it unclear whether a foreign entity, a rogue domestic group, or an insider threat is behind it.
Who was behind the Zero Day attack and why?
In Episode 6, Speaker Dreyer and Representative Mullen explain that the cyberattack was intended to unite a deeply divided country. With Congress deadlocked—failing to pass any legislation for 18 months—Dreyer sought an extreme solution, recruiting Alex and other colleagues.
“They weren’t after money or revenge. They wanted to make the world a better place,” Newman explained, adding that history is filled with disastrous acts that started with good intentions.
As the series progresses, it is revealed that the cyberattack is not the work of a single entity but rather a collaboration between rogue elements within the U.S. government and private defense contractors. Their goal is to manufacture a crisis that justifies the expansion of surveillance powers, military intervention, and sweeping political changes. The attack is designed to sow distrust in democratic institutions and prepare the ground for authoritarian measures.
What is Proteus, and how was it used?
Proteus is a cyberweapon developed by the NSA, capable of inflicting precise brain injuries remotely while remaining untraceable. It was later modified and used in the Zero Day attack.
Episode 6 explains how the malware spread so widely. Kidder, the tech billionaire, deployed it through automatic updates to her app, which was installed on 80% of American phones. From there, it spread via Bluetooth, USB, and other methods.
What causes Mullen’s hallucinations?
While jogging, Mullen discovers a strange object in his bird feeder, raising suspicions that his mind is being manipulated. His hallucinations—including a news anchor seemingly speaking directly to him—suggest interference, but lab tests provide inconclusive results.
The cause of Mullen’s hallucinations remains open to interpretation. According to Newman, the writers intended for Proteus to be the likely culprit, but after seeing the finished show, even he questioned that certainty.
Why does Dreyer try to stop Mullen from revealing the truth?
Before Mullen addresses Congress, Dreyer attempts to convince him that full disclosure would harm the country.
Executive producer Noah Oppenheim explained that Dreyer understands modern America better than Mullen. While Mullen clings to traditional notions of accountability, Dreyer argues that times have changed.
“In an emergency, people tolerate a lot from their leaders if they believe it will help them navigate the crisis,” Oppenheim said.
Modine added that the scene reflects broader themes of trust in government. For democracy to function, there must be faith in its institutions—even when they fail.
Why does Mullen burn his memoir?
After exposing the Zero Day conspirators, Mullen returns home and burns the draft of his memoir. According to Oppenheim, this represents his realization that his congressional speech has already defined his legacy.
Mullen also accepts that he cannot control how history remembers him. Instead, what matters most is maintaining his integrity.
Ending Explained
Alex’s participation in the attack puts Mullen in a difficult position: Should he protect the country by hiding the extent of the conspiracy, as President Mitchell (Angela Bassett) suggests? Or should he reveal the truth, knowing it could cost him his daughter, especially after already losing his son to a drug overdose?
Initially, Mullen delivers a carefully controlled version of events. However, a vision of his son prompts him to change course. He abandons the teleprompter, reads Alex’s confession aloud, and exposes the co-conspirators. The House Chamber descends into chaos, but Mullen stands by his decision, regardless of the consequences.
What happens to Mullen after the speech?
The series ends with Mullen jogging and gazing out at the water, symbolizing his acceptance of the sacrifices he’s made in public service.
While he preserved his integrity, the fallout is immense. His decision to expose Alex may have permanently damaged his marriage. Joan Allen, who plays his wife Sheila, suggested that revealing the truth about their daughter might have been too great a betrayal for their relationship to survive.
Key Takeaways
Newman hopes the series highlights the dangers of justifying extreme actions for the “greater good.” He believes Zero Day serves as a warning about cybersecurity threats and the fragility of truth in modern politics.
Co-creator Michael S. Schmidt compared the situation to post-9/11 America when political unity allowed the government to address the terrorist threat. However, he questioned whether such unity could exist today.
Schmidt explored how a modern cyberattack might play out in a politically divided nation, asking whether the U.S. is prepared—both technically and democratically—to handle such a crisis.
Reviews
Critical Reception:
The series has garnered mixed reviews from critics. On Rotten Tomatoes, it holds a 54% approval rating based on 65 critic reviews, with an average rating of 5.7/10. The consensus reads: “Zero Day has plenty of gravitas thanks to its all-star cast led by Robert De Niro, but this high-concept series’ plotting is a little too goofy for it to take itself so seriously.” Metacritic reports a score of 51 out of 100, indicating “mixed or average” reviews.
Critics’ Opinions:
- Lucy Mangan of The Guardian described the series as portraying “a good man struggling to do the right thing in a world that offers corruption at worst, and only compromise at best.”
- The Hollywood Reporter offered a less favorable view, stating that the series resembles “The New York Times opinion section brought to life in its barely left-tilting centrism.”
- Variety commented that the series touches on relevant themes but lacks depth, stating, “Tech oligarchs, the gerontocracy, podcasters spouting misinformation and the erosion of civil liberties all blur into a muddy soup that’s adjacent to relevancy without ever achieving it.”
Audience Reactions:
Viewer responses have also been mixed. On IMDb, user reviews highlight the strong performances and production quality but express concerns about the pacing and depth of the plot. One user noted, “Zero Day is as good as you would expect it to be with a cast this good. Everything about this series is good from the writing to the cinematography but it’s the pacing that lets it down.”
Conclusion
“Zero Day” offers a star-studded cast and tackles timely themes related to cyber threats and political intrigue. However, both critics and audiences have pointed out that, despite its strong performances, the series may not fully deliver in terms of plot coherence and depth. Viewers interested in political thrillers and Robert De Niro’s work may find it worth watching, keeping in mind the varied reviews.
