Ghost

"The runt of the litter! That one's yours, Snow."

- Theon Greyjoy to Jon Snow

Ghost is one of six direwolf cubs that are found by the children of House Stark. Ghost is adopted and raised by Jon Snow.

Season 1
After five direwolf puppies are found by Robb Stark and taken, one for each one of the Stark children, Jon Snow finds an albino direwolf pup, the runt of the litter. Theon Greyjoy cruelly acknowledges that the wolf is like Snow.

Jon Snow takes Ghost with him when he joins the Night's Watch and uses him to threaten Rast in the middle of the night, warning him that “no one touches Sam”. Ghost stands over Rast, snarling.

When Jon is confined to quarters for threatening Ser Alliser Thorne, Ghost begins to whine at the door in the middle of the night. Jon understands something is wrong and follows the wolf to the Lord Commander's quarters. Suddenly the door shuts and Ghost is locked outside the room. Jon encounters the undead Othor, risen as a wight, and saves the life of the Lord Commander.

When Jon tries to leave and join Robb in his war against the Lannisters, Ghost leaves with him, but also returns back once Jon returns to the Wall.

Season 2
Ghost follows Snow and the rest of the Night's Watch as they venture deeper into wildling territory. While the Night's Watch stay at Craster's Keep, Gilly is scared by Ghost when the white direwolf approaches her, attracted by a dead rabbit she's holding. Samwell Tarly, who had already noticed her, tells Ghost to get away. Later when Jon asks to join Qhorin's raiders, Ghost follows, but as they travel, Ghost separates from the group and ultimately disappears, despite Jon's calls for Ghost to stay with them.

Season 3
Following the attack of the White Walkers against the Night's Watch at the Fist of the First Men, Ghost saves Sam from a Wight, giving Lord Commander Jeor Mormont the chance to destroy the wight with fire.

Ghost accompanies the Night's Watch survivors to Craster's Keep but refuses to enter this time. Instead he ventures back into the Haunted Forest.

In the books
In the A Song of Ice and Fire novels, Ghost is the quietest and stealthiest of the six wolf cubs. While the other wolves are darker-colored, Ghost is an albino and initially appears to be the runt of the litter, though he grows up to be as big as any of the others. Ghost's like-but-unlike nature appeals to Jon as a kindred spirit. Ghost's appearance is said to resemble that of the faces found on heart trees in the North.

Jon finds him separated from his siblings, as he matured faster than the others: he was the first to open his eyes and walk on his own, and was attempting to find shelter away from their mother's corpse. Like Jon Snow, the bastard "outsider" of his family, as the runt of the litter, Ghost had to grow up fast.

In the books, it is emphasized that Ghost is unnaturally silent: Jon tells Tyrion that he named him "Ghost" partially because of his albino coloring, but also because of how little noise he makes. In the books, Ghost is completely mute, utterly silent making no sound of any kind. This wasn't found to translate well to the screen, so Ghost makes noises like growling at Rast in his bunk or whining at Gilly holding rabbits.

Ghost accompanies Jon when he joins Qhorin's scouting group. Ghost participates in the killing of Qhorin and remains with Jon as he infiltrates Mance Rayder's host. Before going with the Wildlings to scale the Wall, Jon orders Ghost to Castle Black, and Ghost obeys.