Game of Thrones is one of the best loved TV shows of all time.
But fans of the show will probably be surprised to know that the noises made by Daenerys' dragons originate from an interesting source: mating tortoises.
The giant flying lizards are the 'children' of Daenerys Targaryen, the beloved Mother of Dragons played by Emilia Clarke, 31.
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What's that sound? Game of Thrones sound designer confirms the noises made by the dragon Drogo are actually recordings of mating tortoises
The hit HBO fantasy show, which is based on the novels by George R R Martin, features three fire-breathing creatures owned by the heir to the Iron Throne, but it is only Drogon that gets its voice from the peculiar source.
Paula Fairfield, the show's sound designer, told WNYC radio show Radiolab on Tuesday: 'The groan of the male actually became, with some work and adjustments and stuff, the basis of Drogon's purr with Daenerys.
'I have sounds I might choose simply by certain personality traits that I might want to push forward. She named that dragon after Khal Drogo, her hot late husband, so Drogon is like her lover. He's whistling at her all the time, he's whistling at her butt and saying, 'Ooh baby.' '
Unexpected origins: 'The groan of the male actually became, with some work and adjustments and stuff, the basis of Drogon's purr with Daenerys,' sound designer Paula Fairfield said.
As a way of bringing the mythical creatures their own flair, Paula decided to give each dragon their own personalities and sounds.
'They're very powerful, they can be very scary, they can be very destructive. But what's kind of magical in Game of Thrones is that the intimate scenes also melt your heart and bring you closer to these characters that should be burning your face off,' she said.
The seventh season of the show saw a dramatic twist when one of Daenerys' beloved 'children' was sadly killed by the Night King, the leader of the White Walkers, as she tried to save Jon Snow from death.
Viseron, who was named after her brother Viserys who died at the end of the first season, was subsequently brought back to life by the Night King and was seen riding him as the series came to an end.
Dragon lover: She named that dragon after Khal Drogo, her hot late husband, so Drogon is like her lover. He's whistling at her all the time, he's whistling at her butt and saying, 'Ooh baby.' '
Sophie Turner, who is also set to reprise her role as Sansa Stark in the show, revealed that the series won't be returning to screens this year.
Season eight of the show was originally supposed to air later in the year, but as the episode's are each set to be 80-minutes long, and filming will not be finished until July, it will no longer be possible.
Fans will have to wait until 2019 to see who wins the Iron Throne.