As usual, if you remove the little-simplified version of the BBC, the story they are talking about is "the Storm God and the serpent". but first:
The Hittites
The Hittites are an old civilization running through the 2000 BC - 1000 BC period. They are great enough to have stopped Ramses II, potentially the most powerful pharaoh ever [You can find a depiction of the Battle of Kadesh opposing the troops of Ramses II and Muwatalli in the recent movie "Exodus"; As every Hollywoodian depiction forget anything there is there instead of the fact there is a huge battle, actually the first largely documented battle, by Egyptian only unfortunately]. Their capital was Hattusa which has been unearthed near the small village of Boğazköy, hence you will find people talking either of Hattusa or Boğazköy or the modern name Boğazkale (I am always using Hattusa).
The general relationship between the "Hittite area" and the Golden Fleece is suspected from the Greeks themselves. Jan Bremmer wrote an article about a specific item called the kursa:
A sheep kurša, then, is essentially a hide with wool, but in the case
of goats it is also “specified as ‘rough, shaggy’ (warhui-), i.e. a
fleece with the long curling hair of an angora (= Turkish Ankara) goat
still on it. The bag has a strap handle by which it can be hung on a
peg, with the contents accessible”. Now the kurša could be hung on
the eyantree, which was most likely a kind of oak but possibly a yew.
It could also be hung in a special building, ‘the house of the hunting
bags’, probably a (room in a) temple, where it had a special place:
‘the place of the god’. In one case, it is worshipped in the temple of
the war god Zababa, what may have given rise to its being hung in the
temple of Ares, but other buildings are also mentioned, and the place
of the kurša clearly depended on local circumstances.
We find survivance of the kursa fairly after the disappearance of the Hittites as here noticed by Herodotus:
7-26: In any case, after crossing the Halys River, [the army of King
Xerxes] entered Phrygia, and on their way through the country they
arrived at Kelaini [...] It is in this city that the skin of Marsyas
the Silenus is suspended [...] It was hung there after Marsyas was
flayed by Appolo.
The Storm God and the Serpent
You will find this story under a lot of names. Hittites were made of a bunch of civilizations, talking different languages (and writing either in cuneiform or hieroglyph as the Luwian language) and it is reflected here. the Storm God will so be:
- Teshub in Hurrian
- Taru for the Anatolians
- The Storm God (of Hatti) for the Hittites (dU in Cuneiform, the "d" being an apposition meaning "god", a star in cuneiform), his wife, Hebat, in Hurrian being the sun-goddess of Arina
On the same level the Serpent is:
- The Serpent
- Illuyanka, which means... serpent in Hittite...
So you will find this story as "Teshub and Illuyanka", Taru and the snake dragon, etc.
There are 2 versions of this story I will shortly describe the second one first:
Second version
Lord Teshub is beaten by Illuyanka who take his heart and eye. Teshub marries the daughter of a poor man and sire a son. This son espouses the daughter of Illuyanka. Teshub asking him to get back his heart and eye. Which he is finally obtaining. Teshub then attacks Illuyanka and kills him, his son coming to him and begging him to kill him with his new family.
I cited this story because of its close connection with Apollodorus's depiction of Typhon vs Zeus. You have the same core elements: Zeus/Teshub defeated and amputated (Heart and eyes vs sinews), they both come back and kick the sorry ass of their arsonists.
First version
The first version is older (for sure) and goes like that (translation by Gary Beckman, I changed to name to Teshub and Illuyanka instead of Storm-god and serpent used by Beckman I also used English standard normalization for the various names):
When Teshub and Illuyanka fought each other in the city of
Kishkilushsha, Illuyanka vanquished Teshub.
[Inara](GB: Inara is
Teshub's daughter, Medea here) prepared everything in great
quantity[...] In the vessels she made abundance. Inara went to the
city of Ziggaratta and she found Khupashiya (GB: here is Jason), a
mortal[...] "I am about to do such and such thing, come with me".
Thusly Khupashiya to Inara "If I may sleep with you, then I will come
and I will do that of you heart"[...]
Inara led Khupashiya away
and she concealed him. Inara dressed herself up, and she invited
Illuyanka [...] So [he] came along with his sons and they ate and
drank [...] They did not want to go down into the lair again.
Khupashiya came and tied up the serpent with a rope. Teshub came and
killed Illuyanka.
As you can see the story is going like that:
An obvious goddess (Medea/Inara) is falling in love with a powerful mortal warrior (Jason/Khupashiya), and help him get rid of a mighty "dragon". Potentially he is later killed (unfortunately the Hittite text, destroyed is not clear).
Walter Burkert talked about that in his fairly excellent Structure and history in Greek Mythology and Ritual:
(page 10) Recently, Volkert Haas [GB: the book is incorrectly spelling
Volker instead of Volkert] has drawn attention to quite another
Greek myth which bears a surprising resemblance to the Illuyankas myth
as told in the "older" version [GB: what I called here the first version]: Jason and Medea. Here, as there, a
goddess - there can be no doubt about Medea's divine status - takes a
mortal man as her lover and the two cooperate to overcome the dragon;
but then the mortal man turns away from his superior spouse, and his
destroyed in consequence [GB: Burkert's personal interpretation
here. The Hittite text says nothing about Khupashiya's death] [...]
I do not think this can be coincidence. But in
spite of the suggestive parallels, it turns out to be impossible to
integrate the Hittite and the Greek tales into one: on the Greek side
there is nothing like the characteristic duality of champion and
helper; thus the whole frame of the combat myth will not fit; on the
other side, the fleeces, though well attested in Hittite Ritual, do
not enter into the tale, whereas the Golden Fleece is the very goal of
Jason's expedition. [GB: Factually the fleece appears in other stories
as Telipinu's one... hence my comments, I thought Illuyanka story was
part of a "Telipinu's matter"]
Generally speaking people specialized (or interested) in Near East old civilization have noticed the fairly strange similitudes between Greek myths and some Near East counterparts:
- The cycle of Kumarbi with the beginning of Hesiod's Theogony
- Ishtar episode in the tablet 6 of the Epic of Gilgamesh with Aphrodite's affair in the song 5 of the Iliad
- Zeus loves with Hera in song 14 of the Iliad with the Enuma Elish
Does not means that one has not to be careful with hurried conclusions.