Star Wars: Episode III – Revenge of the Sith was premiered in the United States on May 12th, 2005.
One of the scenes involves General Grievous (voiced by Matthew Wood) and General Kenobi fighting, where Grievous tells Obi-Wan he’s doomed.
The Jedi replies with “Oh, I don’t think so”.
The meme started emerging online in 2015, with an early example of a YouTube parody, containing the quote having been uploaded on December 10th by Callum Taylor.
Since then, several other parodies have appeared online, as well as exploitables and image macros.
The phrase was first defined on Urban Dictionary on January 27th, 2019.