In my Boom Town review, I complained that:

Are we to assume half the politicians in Cardiff have been bumped off? And a Lord Mayor doesn’t run the council, they chair council meetings and cut ribbons. If Margaret is a directly-elected mayor, her achievement is all the greater.

While my other comments about Margaret Slitheen’s rapid promotion still hold, it is possible that she was both Lord Mayor and Leader of the Council. Until Labuor lost control of Cardiff last year, the Council Leader was the controversial Russell Goodway who for a time held both posts:

Councillor Goodway, who recently stepped down as the 95th Lord Mayor of Cardiff, was the first Lord Mayor in modern times to combine the role with that of Leader of the Council.