Misfires in 1956’s “The Conqueror” abound. In this historical epic, John Wayne plays Genghis Khan, complete with yellowface makeup and a Fu Manchu mustache. The visuals are alarming, and the script isn’t much better. In “The Conqueror,” choppy, confusing dialogue is used to signify non-English speakers. The result would be laughable, if not so blatantly offensive.

Following a string of flops, RKO Pictures was on thin ice in the early 1950s. In 1948, Howard Hughes, who acquired RKO, desperately needed a hit. At the time, sprawling epics were popular at the box office, so the producer decided to make his own. Since Wayne was still signed to RKO, Hughes had little trouble snagging him. According to The Guardian, Dick Powell, looking for a sizable paycheck, came on board as director.

Wayne and Powell’s decisions proved fatal — literally. The atomic testing range at Yucca Flat, Nevada, was just 137 miles from Saint George, Utah, where “The Conqueror” was shot. Per Production Hub, the previous year, 250 kilotons of nuclear weapons were detonated at Yucca Flat, releasing 35,000 kilocuries of radioactive iodine. Federal authorities declared the testing safe, leaving Powell’s team unfazed. Unsurprisingly, of the 220 cast and crew members, 91 developed cancer, and 46 died — including Powell and Wayne. The film earned almost $12 million at the box office, but its notoriety haunted Hughes. In his old age, he reportedly watched “The Conqueror” relentlessly after purchasing all of the remaining copies, perhaps in an attempt to shield someone from the catastrophe.