It's New Year's Eve and on Sydney's Harbour Bridge the most ambitious ever repair of the Bridge's rail corridor has begun. A massive lightning strike takes out a signal box, bringing trains to a halt.

Back at Central, we meet Nasser, a customer service attendant at Central Station. Nasser is first on the scene when a woman faints onto another person standing on the platform.

At Lidcombe station, a man has tragically taken his own life. Although the human tragedy is overwhelming, rail staff focus on dealing with the immediate impact on passengers and the network.

Sydney is in the grip of one of the worst weather events in decades. Over 48 hours, the city is drenched by over 300 millimetres of rain causing chaos on the rail network. As rain buckets down across Sydney, staff at the Rail Operations Centre are bracing themselves for the worst.

In this episode, we mark the anniversary of Australia's worst train disaster. In 1977, 84 people were killed when a passenger train left the tracks and crashed into an overpass at Granville. The day is marked with a sombre ceremony, but it also serves as a reminder of how much safer the network has become as a result of the lessons learnt that day.

We go behind the scenes of the Sydney rail network at night. CSA Tamale is on night shift, looking after the platform servicing Kings Cross, Sydney' s nightclub district. There is only one certainty - as the night wears on, passengers will be more and more boisterous. Sure enough, Tamale must manage intoxicated crowds. Some people seem determined to put themselves at risk by getting too close to the trains, others look to provoke him, while the most inebriated throw up on his platform. Through it all, somehow Tamale manages to maintain his good cheer.

In this episode, we go behind the scenes of Sydney Train's ongoing battle against graffiti. Train tagging costs the network more than $35 million every year to clean off.

For Bea, a transgender woman, the upcoming Mardi Gras parade will be the first time she will be marching as part of Transport for NSW Mardi Gras group. Excitement grows as the day approaches.

It's almost Christmas, one of the busiest times of year for Sydney Trains. With over 3000 train journeys every day, staff at Central Station are working around the clock.

Venture deep below one of Sydney's oldest subway stations, to reveal a secret that sheds light on the city's wartime history.