Filmed over a year, the series goes behind the scenes as the Tube tries to transform itself with a £10bn modernisation programme to cope with record demand. But for its long-suffering workers who deal with passengers at their worst every day, it's more than just a job.
Charlotte controls the Piccadilly Line, one of the busiest, oldest and unreliable lines. Her latest challenge is to find a way to keep it running to capacity, despite drivers reporting problems with the wheels on the trains.
Meanwhile, at Bank station, new recruit Naeem faces furious passengers when there's a strike, and at Holborn, station supervisor Tony attempts a new experiment to cut congestion at rush hour, but will it work?
The Tube: Going Underground, C5, 9pm
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