"Oh my god, hi Sophie Turner, I'm Joe Jonas. I'm a huge fan!" Joe said in a video message. "I honestly have a crush on you but I've got a big question for you. I watch a lot of 'Game of Thrones' and I was wondering -- you're definitely responsible for that coffee cup, right?"
"Okay, let's clear this up!" Turner said, turning to Fallon.
Before she could explain, Fallon showed a still of the scene, where the coffee cup was accidentally left in front of Clarke's character, Daenerys Targaryen. The late-night host then shared a photo of Turner with actress Bella Ramsey, where she is seen holding an identical looking cup. The pic made many fans wonder if the coffee or tea left in the shot was Turner's.
"You know what's funny is that I saw a picture of you holding a coffee cup!" Fallon yelled as he showed the photo. "'Twas you!"
Not only did Turner defend herself, but the actress jokingly named Clarke as the culprit.
"Alright, Detective Pikachu," Turner told Fallon. "This is a spoiler for a couple of episodes ago. This girl dies!" she said, pointing at Ramsey, whose character Lyanna Mormont died during Episode 3.
"[The coffee cup scene] is a scene from the episode after she dies," Turner continued. "So why am I holding this coffee cup. That's in a different scene! And also, we all have the same cups for all of our water and tea and everything."
"So I'm just gonna go with, I mean look who [the cup] is placed in front of!" she said. "Emilia Clarke. She's the culprit!"
When asked if the coffee cup fluke came up in conversation between the "Game of Thrones" cast, Turner replied, "There was just one text and it was from Nikolaj [Coster-Waldau], who plays Jaime Lannister, and he just wrote, 'Great episode. Is that a coffee cup?'"
Turner also talked about her time at the Met Gala and teased her upcoming role in "Dark Phoenix." Check it out in the video, above.
"Game of Thrones" airs Sunday nights at 9 p.m. ET on HBO and catch Turner in "Dark Phoenix" when it hits theaters June 7.