Heads up, there are no actual book or show spoilers in this post but beware links alluding to plot. There be spoilers.

Last year Game of Thrones actress Lena Headey caused quite a commotion when something she posted on her Instagram account was perceived by hyper-vigilant book readers to mean that an exciting character from the novels was coming to the show. Then that character didn’t appear! Even worse, it may never appear! It’s entirely possible that Headey’s “spoiler” was an innocent coincidence and the ensuing commotion just a by-product of a culture of book readers thirsty for clues. But either way, Lena isn’t sorry. How very Cersei of her.

Perhaps inspired by that frenzy (which must be hilarious for the cast and crew), actor Nikolaj Coster-Waldau decided to take a page from his fictional sister’s book and play his own prank on the poor novel readers. But this time, there’s no chance it was an innocent mistake. At the end of filming a promo for HBO Nordic, Coster-Waldau waggled a duck at the camera saying “It’s a spoiler for the book readers. I won’t give anything away. Think about it.” Think about it they did . . . at length. But as Coster-Waldau revealed on Late Night with Conan O’Brien last night, it was all a prank. That duck—like Headey’s Instagram—was a lie.

Book readers will recognize that, once again, those dastardly Lannisters stumbled on an object that just happened to tease the introduction of a big book character the show appears to be leaving out. But as Conan pointed out, a cast member from the show could wave literally any object in the face of a certain kind of book reader and then sit back and watch them chase their tales. That’s how keyed up this fan base is. Fool us once, shame on you Jaime Lannister. The North remembers.

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