David Mitchell Stephen Actor Robert Webb Andrew Actor Louise Brealey Cass Actor Penny Downie Ellen Actor Jessica Gunning Jan Actor John Macmillan Julian Actor Oliver Maltman Mike Actor Geoffrey McGivern Geoff Actor Olivia Poulet Alison Actor Clive Francis Phil Actor Dan Mersh Tom Actor Anthony Head Charismatic Mike Actor Penny Ryder Wendy Actor Kenton Allen Executive Producer Simon Blackwell Writer, Executive Producer George Kane Director