I found Tehran to be a very good espionage tv series and a bit refreshing. Instead of yet another American/British vs Russian spy thriller, here we have something different. In Tehran, we have the Israeli Mossad verses Iran's Revolutionary Guard spy thriller. What I love even more is that the acting cast is authentic middle eastern actors speaking Persian, Hebrew and some English which adds to a feeling of authenticity. Not a bunch of white guys in robes speaking British English like a Bond film. The actors are all very well cast too and excellent performers.
I don't speak or understand Persian and Hebrew, but I found the English AD audio, not to be confused with the standard English soundtrack very helpful because the original voices remain intact thereby keeping vocal stresses, inflections and tensions compared to a Netflix style dubbing. You get more out of it because the English AD audio has a narrator that speaks over, not in place of the actors voices describing what is spoken and describes the action better.