Lower thirds:

00:02 Report by Wade Adams
00:36 Massimiliano de Sanctis | Pyrotechnics expert
01:20 Massimiliano de Sanctis | Pyrotechnics expert

Script:

White smoke billowing from the chimney on the Sistine Chapel -- announcing the election of a new pope. 

It's a tradition passed down through the ages, central to the theatre and drama of the papal succession.

Black smoke for no decision. White smoke for a new pontiff. 

But how do the cardinals control the colour of the smoke?

Massimiliano de Sanctis knows the secret.

+++ SOT Massimiliano de Sanctis, Fireworks expert +++
''Until the election of Pope Benedict, it was done in the traditional way. The ballots were simply burned to make black smoke and they added wet straw to the ballots to make white smoke. Then the Vatican realised that the smoke wasn't intense enough so it designed a controller for PYROTECHNIC smoke.''

The fireworks expert helped create the smoke systems for the election of Pope Benedict and Pope Francis.

It combines a cast-iron stove -- used in every conclave since 1939 -- and an electronic stove for the special effects.

+++ SOT Massimiliano de Sanctis, Fireworks expert +++

Cardinals have black and white pyrotechnics, consisting of six smoke cartridges connected in series, and lasting about seven minutes. After the vote the ballots go into the old stove, from previous conclaves, and the smoke cartridges go into the new stove. Then the cardinal simply hits the "on" button and the smoke will be either black or white.''

Some modern help for an ancient ritual. Will it be black smoke, or white? While the cardinals deliberate, this will surely be the most watched chimney in the world.