A new pope will be selected when a candidate gets a two-thirds-plus-one majority vote by the cardinal electors. White smoke will be sent up the chimney of the Sistine Chapel when that happens, to indicate a new pope has been chosen.

Catholic cardinals from around the world gathered in the Vatican on Wednesday for the start of the conclave, the centuries-old secret voting ritual to elect a new pope to follow Pope Francis, who died April 21.

Some have watched it in the cinema,” one cleric involved said, adding that the movie accurately portrays how the conclave works.