The Tube: Going Underground

Management has decided to crack down on fare dodgers, but it is revenue inspectors Simon and Paul who have to deal with an aggressive passenger refuses to pay at the Angel. At Tottenham Court Road, John is supervising the tricky restoration of Eduardo Paolozzi's famous mosaics. At Walthamstow, the installation of a new escalator is causing bottlenecks. On Poppy Day, Dame Barbara Windsor helps to fund-raise by becoming a Tube driver for the day.

The Tube takes on more than a thousand new staff. But the newbies are joining a system that now faces a level of terror threat unknown in the past.

Engineer Anita hopes she has got her sums right as a new passenger tunnel nears completion, 192 new trains hit the tracks and legend of the line steps down.