The Game of Thrones episode “Eastwatch” was very much a table-setting installment, featuring lots of intriguing conversations that are likely laying the groundwork for major payoffs to come. But while dragons, the Night King, and whatever the hell Littlefinger is up to took center stage, it was actually a scene between Gilly and Sam that could have the biggest repercussions in episodes to come.

In a scene late in the episode, in which Sam is continuing his transcribing busy work assigned to him by the Maesters, Gilly is practicing her reading skills and stumbles across the following information recorded by an older Maester:

“Meynard says here that he issued an annulment for Prince Rhaegar and remarried him to someone else at the same time, in a secret ceremony in Dorne.”

Rhaegar here is Rhaegar Targaryen, a name that has come up a lot in Game of Thrones, but is somewhat confusing to non-book readers as he’s never been seen in the show. Rhaegar was the brother of Daenerys Targaryen and he was married to Elia Martell, sister of dear departed Oberyn—that guy who got his face smashed in by The Mountain.

Rhaegar, son of the Mad King Aerys Targaryen (the one who liked to burn people with wildfire), had a pretty massive crush on Lyanna Stark, sister of our dearly departed Ned Stark. But Lyanna was betrothed to Stark ally Robert Baratheon at the time, and the legend in Westeros goes that Rhaegar kidnapped, raped, and left Lyanna for dead. This led to Robert killing Rhaegar with a big hammer and wiping out the Targaryen line after Jamie Lannister murdered Aerys, which in turn led to Robert Baratheon ascending the Iron Throne via “Robert’s Rebellion.” But in truth, Rhaegar didn’t kidnap Lynanna—they ran off together, wildly in love.

We learned at the end of Season 6 that during Robert’s Rebellion, a young Ned Stark happened upon Lyanna in a tower protected by Rhaegar’s greatest knights. She was dying from childbirth—the child she had with Rhaegar—and asked Ned to promise to raise the child as his own bastard. That child is now Jon Snow, King of the North.

So we knew that Jon Snow wasn’t Ned Stark’s bastard, but was instead the son of Rhaegar Targaryen and Lyanna Stark, which could have given him some kind of claim to the Iron Throne. But now, thanks to Gilly’s discovery, we know that not only did Rhaegar and Lyanna run off together—they were legally married.

This means that Jon Snow was born as the rightful heir to the Iron Throne at the time, and given that Daenerys, sister of Rhaegar, is using her name to claim the Iron Throne, we’ve got a pretty interesting pickle here. It appears that Game of Thrones is planting the seeds for this discovery, as evidenced by Jon Snow petting Drogon at the beginning of “Eastwatch”—the Targaryen blood that so quickly bonded Daenerys with the dragons also courses through Jon’s veins. Moreover, as the son of both a Targaryen and a Stark, he’ll have rightful claim from both the South and the North of Westeros.

So in addition to the murder zombies, suicidal/homicidal/psychopathic Cersei, and a power struggle between Jon and Daenerys about who should “bend the knee,” we now have legal claim to the Iron Throne for Jon Snow—assuming someone connects the dots. This is something Game of Thrones does well, threading the big action set pieces with wheelings and dealings of a personal matter that make the stakes that much bigger.

Where does this lead? Is Jon Snow now destined to sit atop the Iron Throne? Will Gilly’s discovery ever be made public? How pissed is Daenerys gonna be to find out Jon is her nephew? We’ve got seven episodes left in the entirety of Game of Thrones’ existence, so, frankly, shit’s about to get real.