This 'House of the Dragon' character is already dead in the book. Here's how the show changed Gwayne Hightower's story.

Freddie Fox as Gwayne Hightower in "House of the Dragon." Theo Whiteman/HBO Gwayne Hightower (Freddie Fox) is an important character in "House of the Dragon" season three. Gwayne's arc in the show differs significantly from that in George R. R. Martin's "Fire & Blood." If it followed his fate in the book, Gwayne would already be dead. Warning: Spoilers ahead for "House of the Dragon" season three, episode six, and for the book "Fire & Blood." Gwayne Hightower has emerged as an important…