"King Arthur: Legend of the Sword" proved an epic failure in its opening weekend, taking a calamitous $15.4 million in North America, data showed Monday, less than a tenth of its budget.
Movies tend to make by far their biggest box office earnings in their opening weekend, often dropping by 50 percent the following week, meaning the revisionist saga directed by Guy Ritchie, 48, is doomed to be one of the flops of the year.
Starring Charlie Hunnam and Jude Law, the lavish $175 million Warner Bros. movie has an average rating of 4.6 out of 10 from more than 140 reviews collated by movie website Rotten Tomatoes.
"To that hallowed list of great expensive follies -- 'John Carter,' 'Ishtar,' 'Heaven's Gate' -- let us ceremonially add another name: 'King Arthur: Legend of the Sword,'" said Nico Lang of Salon magazine.
The epic's global take was arguably worse, standing at a woeful $45 million by Monday morning from 51 markets, including a disappointing third-place opening in the lucrative Chinese box office.
Ritchie -- once seen as the whip-smart enfant terrible of British filmmaking -- announced himself on the scene with critically acclaimed crime capers "Lock, Stock and Two Smoking Barrels" (1998) and "Snatch" (2000).
He has struggled to maintain his early momentum, earning derision for 2002 romantic comedy "Swept Away," starring then-wife Madonna, while "Revolver" (2005) and "The Man from U.N.C.L.E," (2015) disappointed at the box office.
The domestic performance landed "King Arthur" in third place in the weekend top 10, industry monitor Exhibitor Relations said.
Comedy space romp "Guardians of the Galaxy Vol. 2" dropped 55 percent on its massive opening weekend in the United States and Canada, but still maintained its top spot with $65.3 million.
The Marvel tale of a band of misfit space adventurers accounted for more than half of the cash hauled in by the 12 top-selling movies, placing it a long way ahead of second-placed Amy Schumer and Goldie Hawn comedy vehicle "Snatched," which took $19.5 million.
"The Fate of the Furious," the eighth part of the long-running Universal franchise, managed $5.4 million in the fifth week of a lucrative run that has seen it make $1.2 billion worldwide.
Hanging on for fifth place was Disney blockbuster "Beauty and the Beast," starring Emma Watson and Dan Stevens, which hauled in another $4.8 million, taking it to nearly half a billion dollars in nine weeks.
Rounding out the top 10 were:
"The Boss Baby" ($4.5 million)
"How to be a Latin Lover" ($3.9 million)
"Lowriders" ($2.4 million)
"The Circle" ($1.8 million)
"Baahubali 2: The Conclusion" ($1.6 million)