Shows interesting archaeology, sites and material culture and contextualises them pretty well chronologically. A decent if shallow (naturally due to it being only three parts) story of the Celts across geography and history. Its a bit economically/functionally biased, so doesn't really expand as much on theories around faith, social practices, day-to-day life (even when visiting sites and showing objects that are clearly highly significant) but does place Celtic peoples in the wider geopolitical landscapes of the times in which they lived - which is great - maybe not 'untold' but rarely told.
One thing, however, that is really irritating in the dubbing of certain experts (including some using English - huh!) This means you can't actually hear them speaking, and although I'm not a linguist hearing profs/teachers/communicators in their own words is much more impactful and gives more nuance. The voiceover is not only Americanised (ergh) but on occasion just wrong (I assume its been scripted by someone who isn't knowledgeable about archaeology, history or social sciences - so sometimes its clearly an incorrect 'verbatim' translation) I assume its due to distribution being targeted to an American audience, but as Netflix and globalisation have opened the eyes and ears of that previously closed to international productions market, can we please get to a point where subtitles are used rather than voices stolen.
All in all I enjoyed it,and its a good introduction to the Celts and to a less known European archaeology.