In the season seven premiere of Game of Thrones, Queen Cersei sent a message to Winterfell, demanding Jon Snow come to King's Landing and swear fealty to her. Now we have her summons, and it's just as kind and courteous as you'd expect it would be, which is to say not in the slightest.
HBO has released an image of the full letter that Queen Cersei sent Jon Snow. During the episode, Jon baulked at the notion that he bow down to the newly crowned monarch, and I suspect that's due at least partially to what Cersei wrote:
Image: Making Game of Thrones/HBO
Damn, Cersei, that's cold. And Jon Snow knows a little something about cold: Winter is here, and there's a crap-ton of White Walkers, like, a few kilometres away.
Game of Thrones continues this Monday with the second episode of season seven, "Stormborn".