Ar y Tracs, a festive comedy drama created by Ruth Jones and co-written by Ruth and author Catrin Dafydd, centres on the lives of a Swansea to London train crew. There's Sophie the train manager who has her heart set on becoming a train driver, 'Reality', who works in the buffet carriage and dreams of becoming famous, Dyfrig, the reliable train driver who's a recovering compulsive gambler and Pandora, the ditsy trolley-dolly - not forgetting Ruth herself, who plays a Polish woman, Ingrid, the station café assistant.