Game of Thrones prequel will go into production from June. As per several speculations, the next story from Westeros is going to feature Night King as human. It will show his transformation into the most terrifying King beyond The Wall.
The very first scene of episode one of Game of Thrones featured how a group of rangers was killed by the White Walkers. The very first scene proved that in Game of Thrones, Night King and his army is the true enemy. In the later episodes, Night King went on to kill Daenerys Targaryen's dragon and even destroyed The Wall which Bran The Builder built all those years ago.
In Game of Thrones, the Night King came to Winterfell to kill Bran Stark and with him, he wished to spread the winter night for eternity. However, his evil plans were stopped by Arya Stark, who used her Valyrian steel dagger to stab into his guts. Now that Night King has come and gone, fans are exciting to learn more about him in the upcoming Game of Thrones prequel series which is being created by George RR Martin.
The upcoming Game of Thrones prequel is said to start 5,000 years before Robert Baratheon marched to Winterfell to ask Eddard Stark to become his Hand. The prequel series is said to feature the world after the Golden Age of Heroes and how everything went into darkness.
As per A Story of Ice and Fire, we all know how Children of Forest kidnapped a man, most probably from the Night's Watch and stabbed a dragonglass into his heart. By doing that, they transformed a typical human into a White Walker. The Children of Forest created the Night King to defend themselves when Westeros was invaded by the First Men, who were cutting their sacred trees and slaughtering them.
Even HBO has teased the following about Game of Thrones prequel:
"From the horrifying secrets of Westeros's history to the true origin of the White Walkers, the mysteries of the East to the Starks of legend, only one thing is for sure: It's not the story we think we know."
Game of Thrones prequel is set to air somewhere in April 2020 or April 2021, depending on the production. Till then, we can only speculate as what we will see in the most awaited prequel series.