"Game of Thrones" fans spotted a very unlikely drinking source –– a modern coffee cup –– in Westeros during Sunday night's broadcast. Eagle-eyed viewers on the internet poked fun at the show for its embarrassing oversight.

In the fourth episode of season 8, titled "The Last of the Starks," as characters gathered for a feast at Winterfell following their costly battle, cameras caught (at the 17:40 mark) what appeared to many to be a Starbucks cup just an arm's length away from Daenerys Targaryen.

The show's art director, Hauke Richter, told TMZ on Monday that the cup wasn't from Starbucks, but from a local coffee shop in Northern Ireland, where many of the scenes are shot. Richter added he was "certain" that it was an accident: "We are usually so diligent that this does not happen. The shoot was very hard and demanding and it is likely that after a very tiring ep 3 shoot, this was simply overlooked by an exhausted crew."

For those of you who didn’t think the Starbucks cup gaffe was real, I went back to watch it and—#GameOfThrones pic.twitter.com/xNz2iBHySH — Clarkisha Kent: Benioff and Weiss Hate Account (@IWriteAllDay_) May 6, 2019

HBO offered a tongue-in-cheek statement about the snafu, saying: "The latte that appeared in the episode was a mistake. Daenerys had ordered an herbal tea."

News from Winterfell. The latte that appeared in the episode was a mistake. #Daenerys had ordered an herbal tea. pic.twitter.com/ypowxGgQRl — Game of Thrones (@GameOfThrones) May 6, 2019

Twitter users still blitzed the show's producers about the mistake, considering the current season cost millions to produce and took two years to make it to our screens.

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"You're telling me they had TWO YEARS to put together a decent show and they couldn't even spot the goddamn Starbucks cup in Winterfell??!?!" one user wrote.

"Imagine HBO spending millions on every single episode and being done over by a single coffee cup. Guess Dany didn't get the memo about reusable chalices #GameofThrones," another tweeted.

I thought this might be a joke to make us all rewatch that scene, but nope, it’s real. I took a picture too. It’s at 17:49 and it’s a pretty unmistakable coffee cup. https://t.co/uc8I0zoXiL — Hollie Baggins-Kenobi (@holliebutler) May 6, 2019

The fact that there was a Starbucks cup in tonight’s Game of Thrones that no producers or editors noticed throughout multiple cuts merely 1 week after the DP yelled that the show’s not too dark to see is truly *chef’s kiss* — Jen D'Angelo (@jenlikespizza) May 6, 2019

Others had some fun with the supposed Starbucks connection.

"Guys it's not Starbucks, it's Winterfell's own coffee chain "Dire cup" #GameofThrones," one Twitter user said.

Daenerys Stormborn of House Targaryen, the First of Her Name, Queen of the Andals and the First Men, Protector of the Seven Kingdoms, the Mother of Dragons, the Khaleesi of the Great Grass Sea, the Unburnt, the Breaker of Chains, and Drinker of Pumpkin Spice pic.twitter.com/BOPdolRhXz — Ira Madison III (@ira) May 6, 2019

Even Starbucks joined in on the fun Monday, tweeting,"TBH we're surprised she didn't order a Dragon Drink." The coffee giant recently rolled out the drink, which it describes as a "tropical-inspired pick-me-up" with combination of sweet mango and dragonfruit flavors, plus coconut milk. Then Starbucks tweeted, it's available in the U.S., Canada and the North –– the latter a reference to Winterfell and beyond.