This 10-minute video about how to make croissants is fascinating. Watch at least until the 1 kg sheet of butter is placed on the dough to be folded over several times.
Spoiler: they turn out great, which was unexpected because so often croissants are more bready and dry than flakey and moist, even in France. (thx, aaron)
Source:How croissants are made via kottke.org