The British Transport Police mount a special operation to stop criminals who are running drugs out of the capital. A crack has been discovered on a rail joint at Acton East - if it snaps, it could be fatal. At Paddington, a passenger has fallen between the train and the platform, while at Bristol, a BTP officer must talk down a potentially suicidal woman.

Weekend works at Acton have overrun, a lorry rips the safety barriers off a level crossing as it runs the lights, and 'the flying banana' trails for defects.