Inside the National Palace Museum, Alice and Vivien find a mural matching the image from Liam’s ornament. Next to it is a poetic text that Alice recognizes from Liam’s final blog post, realizing he was directing them to a specific noodle bar in Taipei. After looters storm the museum, they flee, first checking the gift shop to confirm that Liam bought the ornament there. Outside, Alice examines a photo from Liam’s blog and identifies the restaurant’s name, Peach Blossom Spring, from a sign visible across the street.

Meanwhile, President Pardington holds a video call with Chinese President Chen. Pardington asks Chen what he knows about APAI—adaptive predictive artificial intelligence. Chen tells Pardington that as far as he knows, the technology is not yet a reality. Pardington—revealing state secrets over the silent objections of his advisors—tells Chen that US intelligence believes APAI could be used to send worldwide signals such as those that Pangu has been using to sow destruction. By sending secret messages hidden in food items, the two presidents have already identified the real traitors in their administrations. Their public call is a performance for those traitors, in which Pardington falsely blames the deceased Alan Zhou and Chen falsely blames Liu Tongzheng.

At the Peach Blossom Spring noodle bar, Alice and Vivien meet the owner, Ming-na, who is Vivien’s secret contact, Shu-hui. Her husband emerges and is revealed to be Kai-wen, Vivien’s brother, whom she believed had died after the Tiananmen Square protests. Kai-wen coldly accuses Vivien of causing their parents’ deaths, but she explains that their mother ordered her to report them to the Red Guard as the only way for the children to survive. He then reveals he has been her primary informant all along.

In Washington, President Pardington tells his advisors that President Chen is lying and orders them to prepare for an attack. He privately instructs McAllister—who he knows is the traitor—to have Vivien and her daughter eliminated, reasoning that a kill order is already out for them and that his own order will reinforce his deception. In Beijing, Chen does the same, knowing his own MSS head, Wang Lai, is a traitor.

At the noodle bar, Kai-wen recounts that Liam visited him before his death. They realize they unwittingly sent Liam to a traitorous contact who killed him. Alice explains that a coconut bun in Liam’s last photo is a clue, as he had a severe allergy. Kai-wen spots a unique baker’s stamp on the bun, which Ming-na identifies as belonging to The Last Mandarin Bakery in Hong Kong.

Using borrowed identity papers from Kai-wen’s network, the four fly to Hong Kong and take a train into the city. They locate the bakery in a crowded underground food court. Vivien uses the code name “Shu-hui,” and a server leads them through a curtain into a back room.

The baker is Auntie Gugu, Liu’s aunt and the leader of their Hong Kong intelligence network. She explains that Liam met with Liu at her pastry stall, where Liu told him about high-level traitors in both the US and Chinese governments; Liu suspects MSS chief Wang Lai is one of them. When Gugu subtly questions Vivien’s loyalty, Alice fiercely defends her. The group pieces together that Liam and Liu combined their knowledge: Liam knew how Pangu was using the global food supply chain, and Liu knew who was enabling them. They conclude that the attack must involve Adaptive Predictive Artificial Intelligence (APAI).

In Beijing, President Chen waits to confront Wang Lai, but he witnesses a sniper assassinate Wang in the courtyard below before he can act. In Washington, President Pardington and his allies deduce that Pangu’s next attack will target the upcoming National People’s Congress in Beijing, a fact Chen has secretly confirmed. Back in Hong Kong, Alice suggests they flee to Cheung Chau island, the “fish ball island” Liam mentioned in his message to Alice; she believes he deliberately misspelled its name to signal it as a clue. Just as Gugu voices her skepticism, they hear security forces arriving at the bakery downstairs.

Auntie Gugu ushers the group through a hidden escape hatch in the ceiling, staying behind to create a distraction. They flee through the city’s back alleys and board a ferry to Cheung Chau. Meanwhile, an autopsy on Wang reveals something highly unusual in his brain. Unable to reach President Chen, the coroner sends the sensitive report to Liu Tongzheng, who is officially listed as the next in command. Upon arriving at Cheung Chau, the group asks a local for the best curried fish balls, and she directs them to a stall called Kam Wing Tai. It is now the morning of the National People’s Congress.

Secretary of Defense Joanne Clavelle informs President Pardington that a hostile APAI is trying to hack the US Navy’s fleet. She believes the goal is to seize control of America’s nuclear arsenal and launch an attack on China, framing the US as the aggressor. Their only hope is to find Pangu’s base. Pardington sends an urgent warning to President Chen and summons McAllister, intending to force the truth from him.

On Cheung Chau, Alice and her family approach the Kam Wing Tai stall. They enter the back kitchen and repeat Liam’s nonsensical code phrase: “curried fish balls in wonton soup.” A voice from behind a beaded curtain invites them in.

The man is Liu, who confirms that he is running an intelligence network against the current regime, not with the Pangu terrorists. He is devastated to learn of his aunt Gugu’s capture. Moments later, security forces surround the stall. Liu orders everyone to pose as kitchen staff while he confronts the agents outside, using his high-ranking MSS credentials to take command. He instructs the captain to send a false report that all the traitors, including Vivien Li, have been killed in a firefight. They take a photo of Vivien and the other supposed traitors lying on the floor, covered in tomato sauce to make it appear that they are dead, and Liu sends the photo to President Chen.

In Beijing, President Chen receives a series of messages: first, Pardington’s warning about the imminent missile attack; second, another message from Pardington stating that Vivien is their only hope and must be spared; and finally, Liu’s text that the traitors are dead. Believing Vivien was killed despite the warning, Chen tells his family to flee the city, then weeps alone in his office.