The scene opens with Sam Nelson at a train station in the heart of Berlin, where the air is crisp and the streets are blanketed in a layer of snow. It's a day that's far from ordinary in Germany, and Sam is about to experience a rude awakening.
As he prepares to board the subway, he's introduced to Mei Tan, an intern from an AmBank deal in Singapore who clearly left a lasting impression on him. The subway, bound for Honow on the U5 line, brings back old memories for Sam, who's actually here for a meeting at the British Embassy. After what happened with Kingdom and the plane last season, public transport is not exactly a place Sam wants to be right now.
Speaking of the Embassy, Sam is due to meet Arnold Goth for a hearing, but of course, the train is running late. Nearby, police officers storm a den that appears to be used by terrorists. There's evidence of electronics and a lanyard for a train worker. The head investigator, Detective Beck, suspects foul play. Whoever these people are, they're posing as workers at the station.
One man stays behind, claiming to be on a "different shift," wearing one of these IDs. As we later find out, this guy is called Marko. Due to the conditions outside, the driver onboard Sam's train, Otto, is informed to slow down. This journey takes a bit longer than usual, but there are also some suspicious characters onboard.
One comes from a foreigner who's covering their face and wearing a large bag. Whether they're suspicious or not is up for debate, but Sam Nelson is definitely concerned. He tails the guy up and down the carriage before eventually confronting him with the cops.
Sam summons the police to inspect his bag, but the man doesn't do himself any favors by walking away. Eventually, he's thrown off the subway and held at gunpoint. As the train departs, the man reveals that his bag contains nothing out of the ordinary. He's a refugee, but beyond that, he's not a terrorist.
At the next station, a group of students board the train, and among them is a guy named George. He's terrified of the underground and visibly nervous.
Further along the train, there's a big problem. Otto needs to use the toilet at the next station, which is coded as "Code 700." As soon as he gets inside, he tries to call the underground worker, Marko. Marko isn't picking up, but it's clear that Otto is having second thoughts. "I can't do this," he says in a panic.
Eventually, Otto re-boards the train again, but when the station manager questions him, she lets slip that she thought he was suspended. The manager isn't happy and radios control, asking them to replace Otto at the next station.
However, when they arrive... the driver decides to speed on instead. Unfortunately, Marko is down here and he uses an angle-grinder and other equipment to change the lines over. Otto speeds uncontrollably down the tracks, ignoring the emergency stop being pulled by George.
Sam, just like in season 1, finds himself trying to get through to the driver. However, he has a set of keys and manages to get into the driver's cockpit, trying to control the train and slow it down. It's no good though, and Marko manages to divert the train down a different rail.
The train is eventually stopped, thanks to Sam's quick thinking, but this is only the beginning. Sam knows Otto's name and reveals that he's about to hijack this train...
