The Odyssey

Elon Musk is firing shots at director Christopher Nolan over his upcoming movie "The Odyssey" ... joining in with the chorus of trolls on X who are bitching it's an insult that Lupita Nyong'o was cast as Helen of Troy -- AKA the legendary beauty of Greek mythology.

The Tesla billionaire and owner of X went on a spree retweeting -- to his 240 million followers -- posts accusing Nolan of being a "coward" for casting Lupita in a supposed attempt to boost chances to win awards ... including one post by conservative commentator Matt Walsh, claiming "not one person on the planet" sees Lupita as "the most beautiful woman in the world." Sure, Jan.

Elon also endorsed Walsh's other dopey X post ... which argued Nolan knew he would've been slammed as racist if he'd cast a white actress instead -- even comparing the outrage to casting Sydney Sweeney as "the most beautiful woman in Africa."