The Istanbul head of the opposition Republican People's Party, Canan Kaftancioglu, is credited with masterminding the 2019 victory over the ruling party of President Recep Tayyip Erdogan in the city's mayoral elections. The stunning defeat of Erdogan's Justice and Development Party has now led Kaftancioglu to set her sights on ousting Erdogan, if she can avoid jail – as Dorian Jones reports from Istanbul.