The fish stews of southern France are legendary. And in a short trip, I am quite certain I didn't have the 'real' one. Still, the basic idea, simmering a variety of fish and shell fish, in stock, herbs, saffron and tomato isn't that complicated. In fact, this was what a fisherman's wife did, with left overs from the catch -- that's way back when, wives cooked. :)
I had one in the old city of Nice, and it was good, with the rouille and croutons. The gravy was thick, thicker than i thought it would be perhaps since it was un strained. And tasted more of a tinge of tomato than saffron. Perhaps it was inauthentic.
I've been trying fish stews myself -- and now I think I shall branch out into a french inspired version with seer, shark, shrimp, and cuttle fish -- simmered in fish head stock, inflected with karavala (dried fish), ginger and green chille, balanced with vinegar and a little sugar. Watch out for it.