One of the show's most important and loved character, Jon Show's ("Pompeii" star Kit Harrington) fate as a leader will be sealed in "Game of Thrones" season 4 "The Watchers on the Wall." Written by David Benioff and D.B. Weiss, the upcoming Sunday's episode features the men of the wall as they try to defend their fortress from the wildling attack.

WARNING : Full "Game of Thrones" Season 4 spoilers ahead.

Taken from the crow's sworn oath, "I am the sword in the darkness. I am the watcher on the walls. I am the shield that guards the realms of men," GOT episode 9 official synopsis reads: "Jon Snow and the Night's Watch face a big challenge."

Directed by Neil Marshall, the upcoming thrilling episode will feature a massive battle with the crows and Mance Ryder's army as they attack the Night's Watch and Castle Black. Much like the battle with The Viper and The Mountain, the war is going to be a big scale battle with plenty of flight scenes like Marshall's epic "Blackwater" battle.

"Snow has persisted to stand up for what he believes is right and seems to be pretty ready for the battle to commence," Cinema Blend wrote for Snow's upcoming reunion with Ygritte. "But with his former lover Ygritte on the way, the battle should be a whole lot more complicated."

The video's preview features a voiceover that notes, "Love is the death of duty," gives away the former lover's reunion in the battle. Switching between the perspective of the show's major players, the show's previous episodes allows Snow to warn the others of the Wildling attack and even mentioned the giants who will help the Wildling to break The Wall.

Throughout the four season, episode 9 is a penultimate chapter as it features big scenes and epic twists of the series. Ned Stark was beheaded in season 1, the battle of Blackwater in season 2 and Starks was massacred in the Red Wedding in season 3.

"Game of Thrones" season 4, episode 9 will return to HBO this Sunday, June 8.