Game of Thrones season 7 episode 4: Something is going on with this dagger

It has a curious history in Westeros

A still from the season 7 episode 4 trailer

If the principle of Chekhov's Gun can be applied to a dagger, then somebody in Westeros is getting knifed before Game of Thrones season 7 is out.

You can be forgiven for forgetting about 'unnamed Valyrian steel dagger', as it hasn't featured in the show since season one, when the catspaw assassin planned to use it in his assassination attempt on Bran Stark.

After the bid failed, Catelyn noticed the weapon was an intriguingly fine one made from Valyrian steel and with a dragonbone hilt, and took it King's Landing for Ned to inspect. It somehow ended up in the hands of Petyr "Littlefinger" Baelish however, even being held to Ned's throat during that double-crossing scene in the throne room, and is presumed to still be in his possession.

So why the sudden interest in a largely forgotten weapon?

Firstly, this lingering shot of it depicted in a book in the Citadel library in s07e01, on the page before the one containing Sam's dragonglass discovery:

This isn't just me reading too much into the shot either - here's Sam actor John Bradley on the filming of it:

"When we were shooting that scene, I was literally told 'make sure that you linger on this page.' They were shooting over my shoulder and said make sure to linger on it. Make sure we get a good shot of this page before you turn the page over."

The showrunners were clearly keen to emphasise the dagger, and it got another nod in the trailer for episode 4, 'The Spoilers of War', being unsheathed quite ceremoniously:

If that's Littlefinger in the shot, why is he getting a knife out in Winterfell? And is the fact that it is made from two substances known to hurt White Walkers significant? More excitingly still, that could be Arya utilising it, as she appeared to be wearing the dagger on a recent Entertainment Weekly cover:

Littlefinger isn't strictly on Arya's list, but perhaps she will quickly tire of his conspiratorial whisperings when she returns to Winterfell this week?

Game of Thrones continues sunday nights on HBO, Sky Atlantic and NOWTV.