How many porn stars have appeared on â€˜Game of Thronesâ€™?

The guys behind "Game of Thrones" have gone to interesting lengths in their efforts to cast the right actors.

For example, in Season 4, the character Gregor Clegane will be played by an Icelandic strongman competitor called Hafþór Júlíus Björnsson. The man has never acted before in his life.

Meanwhile, at least six female characters on the show have been played by current or former porn stars.

Warning: There may be some spoilers below, depending how much "GoT" you've seen.

Sibel Kekilli

Photo: FilmMagic

Kekilli appeared as a guest star in Season 1, and has since become one of the show's regular characters. The German native plays the role of Tyrion Lannister's mysterious, headstrong lover, Shae.

Kekilli appeared in a series of adult films more than a decade ago.

Samantha Bentley

Photo: Getty Images

Bentley is a British porn star who has won several awards for her work in the adult industry. She was even crowned "Best Female Performer" at the UK Adult Producers Awards last year. Bentley has been named in the show's official cast, but her role has not been specified yet.

Jessica Jensen

Photo: YouTube

Jensen entered the adult industry in 2011 and was named "Best Newcomer" at the Producers Awards the following year. Much like Bentley, she has been included on the list of cast members for Season 4, but we don't know whom she'll play.

Aeryn Walker

Photo: YouTube

Walker is an Australian amateur porn star with a penchant for "costume play." She will appear as one of Craster's wives in Season 4. If you've watched "Game of Thrones," you'll know Craster as that creepy wildling who lives north of the wall.

Maisie Dee

Photo: YouTube

Dee is another British porn actor. She played the character Daisy, one of Petyr Baelish's prostitutes, after joining the "Game of Thrones" cast in Season 2, and was famously on the receiving end of King Joffrey's sadism. Dee will not be appearing in Season 4.

Sahara Knite

Photo: YouTube

Knight worked as a clothing technologist for six years before joining the adult industry. She was then hired to play another of Baelish's prostitutes. Knight appeared in one of the show's most controversial (and popular) sex scenes, alongside Esme Bianco, but her role ended in Season 2.