With two episodes of HBO's wildly popular "Game of Thrones" to go, puzzled fans took to social media on Monday after Daenerys Targaryen was joined at a wooden banquet table by a rogue coffee cup.

Jokes, spoofs and critiques quickly followed the appearance of the cup -- taken to be a Starbucks coffee by many who noticed -- in the fourth episode of the eighth and final season.

"Seriously, they have Starbucks in Winterfell," one commenter wrote on Twitter, while others lamented the slip-up after waiting two years for the eighth season to air.

HBO spoke up as the mistake went viral, tweeting that "the latte that appeared in the episode was a mistake" and playfully adding that Daenerys -- played by British actress Emilia Clarke -- had ordered an herbal tea.

Meanwhile, executive producer Bernie Caulfield told WNYC radio she couldn't believe the error, saying that "our on-set prop people and decorators are so on it 1,000%."

"We're sorry!" she said. "If that's the worst thing that they're finding, we're in good shape."