Guest Stars Katy Brand as Medusa Michelle Gomez as Mary Queen of Scots Selina Griffiths as Marie Antoinette Michelle Gomez as Margaret Thatcher Sharon Horgan as Tammy Wynette Sharon Horgan as Unity Mitford Reece Shearsmith as Princess Margaret Morgana Robinson as Venus Morgana Robinson as Anna Nicole Smith Samantha Spiro as Jessica Mitford Samantha Spiro as Betty Knox Doon Mackichan as Catherine Howard Frances Barber as Elizabeth I Sophie Ellis-Bextor as Nancy Mitford Dustin Demri-Burns as Joe Keppel Kathy Burke as Queen Mother Seb Cardinal as Janis Joplin Seb Cardinal as Jack Wilson