P.C. Aidy Young patrols the station keeping order, Michael from Network Rail responds to reports of a suspicious bag. An aerial survey specialist uses thermal-imaging to inspect hundreds of miles of track by helicopter.
Things kick off with a day of severe disruption on the railways as a train loses power on the East Coast Main Line, blocking services in and out of King's Cross and a domino effect causing problems all along the Line.
A specialist fire brigade response team are called after a woman falls between the platform a moving train and becomes trapped on the tracks. Staff are tested when a Tube strike hits London.