The West Coast Mainline is the busiest route in Europe - linking London to Glasgow with Birmingham, Manchester and Liverpool in between. Despite an unprecedented £9bn upgrade just a few years ago, already this line is straining under a jam-packed schedule and ever growing passenger numbers. Quite simply, this line is full up. With 4,000 trains on the route every day, signal boxes that still rely on Victorian lever technology, and the window for maintenance smaller than it has ever been, the staff are under pressure just to maintain the status quo - and when engineering upgrade work happens to fall on the FA Cup final weekend, the railway staff find themselves even more unpopular than usual. With so many trains squeezed on this route, just a small problem can quickly throw the line into chaos. When a train breaks down in the middle of the line, train manager Matt has to roll up his sleeves and go trackside to check the train, while the staff on the customer information point at London Euston face down the increasingly frustrated passengers.