Netflix is streaming a Welsh language drama for the first time.

S4C's Dal y Mellt is a crime drama airing under a new title, Rough Cut.

It is the first solely-Welsh language production to be shown on the global streaming service.

Dal y Mellt – which translates as Catch The Lightning – was released as a box set on S4C Clic and BBC iPlayer in October and is an adaptation of Iwan 'Iwcs' Roberts' debut novel.

Set in Cardiff, Soho, Porthmadog and Holyhead, it follows a group of misfits as they come together to pull off a heist.

S4C's head of scripted Gwenllian Gravelle said it was a milestone for the channel.

"There's an appetite for more drama, and I think we offer something unique through our productions," she said.

"This means our dramas will have more exposure.

"It possibly means more co-productions with the big streamers. That means bigger budgets for us."

Netflix said it hoped it could play a role in helping to "promote and preserve the Welsh language".

Roberts also wrote the TV script and co-produced the drama with Llyr Morus.

Film and TV critic Lowri Cooke said: "I do believe that we're standing on the edge of a golden era. But we have to have the internal confidence to kick the doors wide open.

"Some of the most exciting elements are the Welsh genre productions we see in our cinemas. That is, drama, horror and thriller productions in our own language. That's mind blowing."

Nearly a decade ago the English version of the detective thriller Y Gwyll/Hinterland was sold internationally, with a number of bilingual series since following the same pattern.

It was produced and directed by Ed Thomas, whose latest production Pren ar y Bryn/Tree on a Hill is also being filmed in both languages.

"At the moment, we have the same model as we had with Y Gwyll, filming back-to-back," he said, adding an English version could been needed to secure funding.

While taking pride in the success of Dal y Mellt, Mr Thomas said there was "a long way to go" before productions got enough funding for Welsh-only versions that sell internationally.

"That's what we have to target is to ensure, that if we're on Netflix or Apple or Amazon Prime or whatever it is, that they also follow it up with real investment in the Welsh language."

Ms Gravelle said now was the time to take advantage of audiences getting accustomed to watching programmes in different languages using subtitles.

"As we've been watching over the last few years, really popular series that aren't in English like Squid Games, Lupin and Money Heist that shows if you have a good story, and if you have good drama, it will travel."