Posted with permission from Newsweek

This story contains spoilers about the latest episode of Game of Thrones, “Eastwatch.” If you don’t want plotlines spoiled, click away now.

Oh, Littlefinger, what are you up to?

Sunday’s Game of Thrones featured the scheming Petyr Baelish—played by Aidan Gillen—attempt to sow seeds of distrust between sisters Arya (Maisie Williams) and Sansa Stark (Sophie Turner).

Of course, he needn’t try too hard, because Arya is already concerned that Sansa is getting a little too comfortable in her role as Lady of Winterfell in Jon Snow’s absence. But Littlefinger played a dangerous game to further drive the two sisters apart in “Eastwatch,” perhaps because he understands that Arya, with her knack of cutting through the BS, is a threat to his position as Sansa’s adviser.

Littlefinger’s latest trick was to pretend he was hiding an illicit letter, written by Sansa during her time in King’s Landing with Joffrey and Cersei Lannister in Season 1, and make it seem like Sansa wanted it hidden.

Littlefinger hid the note in his bed chambers and then looked on as Arya rifled through his belongings to find it. The note, from Sansa to her now-dead brother Robb Stark, doesn’t show Sansa in the best light. In it, she asks Robb to pledge fealty to Joffrey and House Lannister.

Though we couldn’t see the note in its entirety on screen, Reddit user Opa1979 deciphered its contents. Read below:

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

Back in Season 1, after Robert Baratheon died and Sansa’s father Ned was charged with treason, Cersei threatened Sansa into writing a letter back home to her mother Catelyn and brother Robb, to convince them to support Joffrey:

Littlefinger was present when Sansa wrote the letter, which Robb rightfully dismissed as being written under duress when he received it, so he would have known of its existence.

Earlier in Season 7, in the third episode, “The Queen’s Justice,” current Winterfell maester, Maester Wolkan, casually mentioned that his predecessor Maester Luwin "kept a copy of every raven's scroll” sent to Winterfell, which explains how Littlefinger got his hands on the letter.

When Littlefinger received the note he said, “Lady Stark thanks you for your service,” presumably aware that Arya was eavesdropping. He deliberately made it sound like Sansa wanted the letter hidden away.

The contents of the letter would cause Arya more concern about Sansa’s loyalties. She wasn’t aware that Sansa wrote it under duress and will now be questioning whether Sansa has been allied with the Lannisters this entire time.

This may not be a happy homecoming after all.

Game of Thrones airs Sundays at 9 p.m. on HBO.

For more Game of Thrones coverage on Newsweek, click here.