Siobhan Finneran and Sarah Lancashire would later play sisters in Happy Valley (2014). Jason Merrells and Derek Riddell also appeared in the series.
Lesley Sharp and Siobhan Finneran appear in the first two series as friends Trudy Graham and Julie O'Neill. Both had their breakthrough roles in Rita, Sue e Bob in più (1987), in which Finneran plays the titular character Rita, who has an affair with Sharp's character Michelle's husband Bob.
John Simm, Philip Glenister, Dean Andrews and Marshall Lancaster would later co-star in Life on Mars (2006). Jack Deam and Marc Warren made guest appearances.
Paul Abbott's involvement with the series decreased over the last two seasons, as he was busy with other projects.