Halt! This post is dark and full of spoilers for the Game of Thrones season seven finale, “The Dragon and the Wolf.” If you haven’t watched it, turn away and head back to the Citadel to complete your homework.

The Lannister siblings have never been at peace with each other. Jaime and Cersei may have a certain, uh, understanding, but Tyrion‘s been on the outside since birth. Cersei hasn’t been a fan of her younger brother since his arrival caused their mother to die, and she’s only found more reasons to hate him as time’s passed. But, Cersei and Tyrion shared a moment in the finale. Maybe it’s because Cersei’s desperate to cling to the few family members she has left, or maybe it’s because Tyrion brought an enticing option to the table and is now working with Cersei behind Daenerys‘ back.

I noticed the Tyrion and Cersei team-up theory posited on Twitter and on Reddit by ndotny, and it’s not entirely out of the realm of possibility. Tyrion’s never cared for his sister and has thought about killing her multiple times, but he’s never followed through. Cersei could have uttered a word to the Mountain in “The Dragon and the Wolf” and ended Tyrion’s life, but she didn’t. They’re still family, and with Cersei playing up her supposed pregnancy, Tyrion was inclined to show kindness. He also mentioned how he truly loved her children.

But maybe not Joffrey. Because, obviously.

Cersei may not actually be pregnant, but she’s using the possibility to her advantage. She’s been placing her hands on her stomach at key moments to ensure the gesture is noticed. While she probably intended to use the whole carrying-a-baby thing to maintain her control over Jaime, it also came in handy useful with Tyrion.

Think about it. As far as Tyrion knows, Daenerys can’t have human, non-reptilian children and that means no heirs. When it’s not clear who’s next in line, wars happen. Westeros has had an abundance of fighting already. Tyrion wants the world to be a better place, and he likely wants that to last longer than the reign of a single ruler. Tyrion also knows Cersei isn’t going to help with the undead problem for selfless reasons. Saving her entire realm from the Night King’s army isn’t enough for her to send the Lannister army to help. There has to be something in it for her.

Something like ensuring her child will have the most powerful seat in kingdoms.

Like basically all the characters in Thrones, Tyrion has to weigh a pile of unsavory options. He has to consider the good of the many versus the good of the few several times a day. To get Cersei out of the way and to stop her from scheming against Daenerys, I could see him making an executive decision without consulting Dany and promising Cersei that her child will be the heir to whatever Daenerys leaves behind.

This theory also explains why Tyrion was creeping outside the door while Dany and Jon were embracing their inner dragons. I don’t think any sort of jealousy caused him to lurk. What if it’s because he was concerned about their hook-up leading to a baby and therefore causing his agreement with Cersei to fall apart? Like Jon pointed out, maybe the witch who told Dany she wouldn’t birth any other children was an unreliable source (hey, good job, Jon for having a single smart comment).

If you want to fit this puzzle piece into the existing Westeros framework, you could say that Tyrion will be the third treason from Dany’s visions in the House of the Undying. She was to know three treasons: “once for blood and once for gold and once for love.” Blood and gold are believed to have happen, but the love part? If it’s not romantic love, that could be tied to Tyrion. Emphasis on could.

Of course, after giving Jon a hard time for not lying, Tyrion could have told Cersei whatever he thought she wanted to hear and not mean any of it.

Do you think Tyrion went behind Dany’s back? Visit the comments and let us know if you think this theory holds water.

Ready for more Game of Thrones?

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Images: HBO, Tumblr/Di, Black Panther Storm