I still can't find an air date for any other country as yet, but it will start on Friday at 10pm on Showcase in Canada. Their website is calling it part 1 of 2 rather than the 4 parter that has been touted up until now, but as it has a two hour slot I am guessing that they are showing double episodes. I can't find the trailer anywhere yet, although I understand that the channel have been showing it for the last week, so here's the trailer we published back in September.
Set between modern day France and 13th century Carcassonne, two women's lives intertwine through history. Modern-day archaeologist Alice Tanner discovers skeletal remains and a labyrinth-engraved ring in a cave, attracting the attention of unscrupulous individuals. In 1209, newly married Alaïs Pelletier du Mas protects three sacred books that reveal a world-altering secret.