On an off-peak train, Geri gets into an argument with a young lawyer in one cabin, while Jacob who is out playing truant unexpectedly chances upon his mother and her client in another. The train comes to an abrupt stop in the middle of the tunnel and the passengers find themselves being held hostage by four masked hijackers.

Leader Black calls through to KMRT's headquarters which the police have taken over, and demands to speak only to negotiator Chia Wen Si. The police scrambles to find Wen Si but she has to earn the trust of Joseph before she can take over the negotiations. The situation turns when Black realises he has been played out by the police.

The hostages are forced to choose a volunteer, and Ray offers his unpopular opinion. In exchange for the release of 18 hostages, Black demands for a live media conference to address the public directly. Meanwhile, Wen Si identifies prime suspects behind the hijack. Shawn delivers food into the tunnel and attempts to communicate with a hostage.

The police make contact with a hostage holding on to a hidden phone. In his live streaming, Black asks for the media to investigate the criminal acts of four prominent millionaires. Wen Si succeeds in guessing the identity of the leader, but the latter is riled up by the authority's attempts to rock the boat. Wen Si tries in vain to convince him of the authority's cooperation.

Joseph and his team deal with the fallout after a rescue attempt goes awry. Boon Wee tries to help the authorities but puts his own life on the line. The hostage-takers unmask themselves in front of the passengers as they single out Titus. John asks to speak to his father Susilo Bhagawan.

A devastated Titus withdraws himself after his father curtly leaves the negotiations. John reveals the reason for designating Wen Si as the negotiator and unveils her painful past. Ray's perverted obsession is revealed, and he faces judgement. In a desperate attempt to save his own skin, he exposes the deed of another hostage. Jana announces that there is a certain development onboard the train.

Holding a hostage at gunpoint, John pushes the hostages to hand over the informant. Over at the headquarters, Jana urgently briefs the team about a Point of Interest onboard the train in possession of critical information that could jeopardise national security. With lives at stake, Joseph orders NAGA to storm the train right away. A twist of events confounds everyone.

A new leader emerges among the hostage-takers and tries to turn the hostages against the authorities. Left hanging on to his life, John questions their cause and hopes for the rest to stop. Wen Si persuades Joseph to let her negotiate in person in exchange for more hostages released.

Wen Si finally comes face to face with Geri on the train. She tries to seed doubt in Geri and plays the hostage-takers against each other. Meanwhile, Jana uncovers troubling information about the organisation that the hostage-takers had pledged allegiance to. The authorities intercept a meme sent out from the train, with an encrypted message beneath.

Raj grows frantic even as he continues to make contact with a mysterious higher-up. He is reminded of the cause, and is determined to get his revenge. Still reeling from despair and betrayal, Titus volunteers to join the dark side and Val makes the most of this opportunity. With Wen Si's help, Geri exposes the deeds of those who were once closest to her in a public livestream.

Geri discovers a deeper, more ominuous agenda of AFV and its links to global catastrophes. Raj grows fearful that his true intentions might get exposed and silences a threat. Geri tries to convince Raj and Val that they were being played, but Raj soon catches on to it...

Raj convinces Val that Geri has sold them out. Initially swayed, Val later decides to trust no one but herself and seizes control over the negotiations. With Val now at the helm, where will the remaining hostages end up?