Warning: This post contains spoilers about "The Spoils of War," Game of Thrones's fourth episode in season 7, plus predictions about future episodes. If you’re not caught up, stop reading now.

Game of Thrones's Jon Snow, a man tragically incapable of knowing anything, may be on the verge of finally learning something about himself: the secret of his lineage. A brief moment in the teaser trailer for "Eastwatch," the fifth episode of season seven, hints that Jon could begin to piece together the truth about his Targaryen ancestry as soon as next week.

The season six finale confirmed the long debated R + L = J fan theory for the audience. Jon is not Ned Stark’s bastard, but the illegitimate child of Lyanna Stark and Rhaegar Targaryen. That makes him a Targaryen by blood—and Daenerys's nephew. Neither of them know this, of course, and Daenerys told Jon she was the last Targaryen as recently as last week’s episode.

But, in a snippet of the episode 5 teaser, HBO hints at a moment in next week’s show that could put the pair on the path to enlightenment. About 15 seconds into the trailer, Jon comes face to face with a dragon for the first time.

It’s possible that Drogon, the dragon Daenerys rode into battle in epic fashion in "The Spoils of War," will recognize Jon's Targaryen blood. Drogon may behave differently around him, showing the same kind of deference that is usually only reserved for Daenerys. If the queen realizes Jon and Drogon have a connection, she may offer to let him ride another dragon—perhaps Rhaegal, the one named after his father. That would move us one step closer to the completion of the Three-Headed Dragon theory, which predicts a rider for each of Daenerys’s three dragons.

Jon’s discovery of his lineage wouldn't come a moment too soon. With Jon riding into battle on a dragon’s back, the Night King’s army wouldn't seem nearly so unstoppable. It might also put the brakes on the force of attraction that appears to be pulling Jon and Daenerys together since their jaunt through the caves of Dragonstone. It’s unclear if this series has room for another incestuous main character couple, but Kit Harington has confirmed that the King in the North is definitely crushing on his aunt.