Off-duty police officer Laurie Franklin finds herself caught up in a strange sequence of events after a person falls in front of her train.

One day later the police are struggling to find out more about how the victim died, and the abandoned baby's identity is still a mystery.

A week on, the police carry out a reconstruction of events. Meanwhile, family tensions mount for Nusrat and Danny.

A month has passed. A royal visit to the town turns nasty, and one character receives a visit from someone who seems to know more about what happened on the bridge.