Couple craft fantasy languages for screen

From Dothraki and Valyrian in "Game of Thrones" to the Chakobsa desert tongue in "Dune," American couple David and Jessie Peterson have devised numerous imaginary languages.

Immortal lines from the "Game of Thrones" scripts such as: "You are my last hope, blood of my blood," plunge viewers deeper into the series' fantastical world when uttered in the original Dothraki, "Yer athzalar nakhoki anni, zhey qoy qoyi."

In Dune, the Fremen desert warriors roll the "r" in their Chakobsa tongue, the name comes from a real ancient hunter's language that inspired author Frank Herbert in writing the original series of "Dune" books.

But Herbert and Game of Thrones novelist George R. R. Martin only included a few words of these fantasy languages in their pages, it was the Petersons who fully developed them for the screen.

"Languages can be fun. Often, I think languages are treated very seriously," said David Peterson.

The use of language creators in films dates at least to 1985 when Marc Okrand created Klingon for that alien species in Star Trek.

It has since taken off in numerous fantasy series but few people make a living from the work.

A trained linguist, Peterson landed his first paid assignment to develop Dothraki by winning a competition in 2009.

Speaking at a masterclass during a television series festival in the French city of Lille, the Petersons described how they devise languages by discussing the characters' environment, backgrounds and the objects they use.

From there, "we extrapolate," David Peterson said. With short turnaround times for filming, the Petersons share the work.

Creating a language means more than just making up words. The couple start by building grammar, including word genders and...