From Rhashan Stone's
facebook news page:
City Hall - begins filming this week. It stars Olivia Williams, Rhashan Stone, Martin Shaw & Lucy Punch. Commissioned by Sky, it is Rhashan's debut screenplay as a writer. It tells the story of Dorothy Green, the unconventional housewife who becomes London's first female Mayor.
source Rhashan Stone, in case you didn't know, is Olivia husband. Congratulations :D