Here's what is written in the scroll Littlefinger so desperately wanted Arya to find.

Warning: Spoilers ahead. But you knew that already, right?

While the latest episode of Game of Thrones gave us some surprising news about Jon Snow’s claim to the Iron Throne, there was another important scene that could spell bad news for the Stark sisters.

It seems Littlefinger is up to his old tricks again (seriously, why does he have to be so smart?) and is trying to drive a wedge between the newly reunited Sansa and Arya.

As a stealthy Arya spies on Lord Baelish doing business around Winterfell, we learn he’s found a scroll of which only one copy exists, and he hides it in his room.

Naturally, Arya finds it and reads it and once she does, she looks clearly distressed.

That's because some clever fans have discovered the note is actually one Sansa wrote to her brother Robb way back in season one, right after their father Nedd Stark was arrested for treason.

"Robb, I write to you with a heavy heart. Our good king Robert is dead, killed from wounds he took in a boar hunt," Sansa's letter reads.

"Father has been charged with treason. He conspired with Robert's brothers against my beloved Joffrey and tried to steal his throne. The Lannisters are treating me very well and provide me with every comfort.

"I beg you: come to King's Landing, swear fealty to King Joffrey and prevent any strife between the great houses of Lannister and Stark."

For Arya, who is hellbent on destroying the Lannister name, the note doesn't read well.

In a post-episode interview, showrunner and writer D.B. Weiss explains the scheme, pointing out that Littlefinger is using everything at his disposal to get between the two Stark sisters.

"She gets roped into spying on somebody who is actually leading her by the nose to something he wants her to have," he said.

"He's looking for a way to prevent this sister bond from developing further, because the tighter that bond is, the more definitively he is caught on the outside of it.

"All he needs to do is give Arya cause to display real rage towards Sansa and he knows... when Arya starts to act dangerous and act angry, he knows where Sansa's going to turn."

Fans of the show might remember that Sansa only wrote the note after threats were made to her father's life by Cersei.

(You can watch the scene where she is persuaded to write to Robb here.)

Luckily, Robb Stark was able to see through the letter and determined (with the help of Maester Luwin) that Cersei had a hand in the note's contents.

Here's hoping that Arya can do the same.

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