The most famous event happening during your stay at the festival is the Christmas market of course. During Friday to Sunday there are some dance and choir performances too. Market is open everyday. Here is the programme: http://christmasmarket.ee/en/
Here is the Visit Estonia link: https://www.visitestonia.com/en/tallinn-christmas-market
Do not miss on 23.11 when the Black Food Festival in Tallinn,when all the food and drinks that they serve are black.
https://www.visitestonia.com/en/black-food-festival-in-tallinn
Robotex starts on 29.11. More informaiton here: https://robotex.international/
Also Christmas Jazz starts on 29.11. https://www.jazzkaar.ee/en/
Hope these help, have a pleasant stay in Estonia!
20.11.2019 | Tallinn Black Nights Film Festival's blog