Game of Thrones season 7 is really ramping up the stakes for our heroes, and everyone can feel the tension, knowing that our tale is almost at its end. And speaking of ends, poor Dany may meet hers after a betrayal from within her most trusted circle - if a certain fan theory is correct.
Warning: The theory is based on information found within the books, and thus could be considered SPOILERS
Reddit user Jamesik points out that in the books, Daenerys visited the House of the Undying and was given a prophecy that she would be betrayed three times: once for blood, once for gold, once for love. The former two have seemingly come true (the death of Dany and Drogo's son is blood, Jorah selling her out to assassins is gold) but the third has not. Yet.
Jamesik theorizes that the betrayer will be Tyrion, who still loves his brother Jaime - and as we saw in episode 4, Jaime is in serious danger simply by standing in Dany's path. However, user goodguy_asshole (Reddit users really have the best names) suggests it will be Missandei who betrays Dany in order to save her love, Grey Worm.
Now, one thing worth noting is that although Daenerys visited the House of the Undying in the show, she did not receive the prophecy there (at least that audiences saw). That doesn't mean the prophecy doesn't exist or that the show won't follow its cues, but it's not widely-known information at this point. Also, prophecies are notoriously finicky when it comes to interpretation - some fans are arguing that the blood and gold betrayals are either related to different events or haven't come true yet, so really it's anyone's guess what will happen to our dear Khaleesi.
But maybe start clutching your pearls a little tighter, just in case.