McDonald's has karate-chopped the rumors and quashed pleas to bring McSushi to North America.
After a Twitpic surfaced Wednesday showing a tray of sushi rolls, miso soup, wasabi and soy dipping sauces in McDonald's packaging, the Twittersphere was abuzz with speculation that the burger chain was entering the final frontier of the fast-food market - raw fish.
Reaction was swift among Tweeps with #McSushi trending worldwide on Wednesday.
Lord_Voldemort7 was as skeptical as any dark lord would be, tweeting: "Are you people trying to kill yourselves before I do it?"
But McDonald's official Twitter feed quelled the rumors late in the day saying "there are no plans to bring McLobster or McSushi to our US menu."
That may well disappoint Brandi Wheeless, who tweeted "What the wha??? Party in my belly!"
McLobster sandwiches - which were also trending Wednesday and Thursday - have been available in the maritime provinces of eastern Canada and New England in the US as seasonal items but they're a novelty for McDonald's diners elsewhere.
Selling regional-specific items is a strategy long used among fast-food outlets. The McDonald's burger menu in India, for example, offers vegetarian or chicken and fish-based items.
Meanwhile, KFC also sells bowls of congee - a traditional Chinese rice porridge with pork, pickles, mushrooms and preserved egg - at their outlets in China.
Indian outlets of Pizza Hut are likewise predominantly vegetarian or use chicken as their protein.