Kathleen Rose Perkins (Carol Rance), Daisy Haggard (Myra Licht) & Ben Miller (as himself) all worked together on Ballot Monkeys (2015) as Melanie Buck, Christine Proctor & Kevin Sturridge respectively.
Because each episode in each season is named only by "Episode [Number]", there are 5 different Episodes named, "Episode One", 5 named "Episode Two", etc... This is very unusual; normally one can refer to an episode of a TV series by its name to uniquely identify it without having to add in extra information such as which season it is in in order to differentiate it from multiple other episodes as you would have to do here.