It’s being called India’s “Star Wars,” smashing box-office records worldwide. The wild superhero epic “Baahubali 2: The Conclusion,” which opened at the end of April, has become the highest grossing Indian film in history, and its breakthrough in the U.S. may be just as significant.

With a $10.3 million opening weekend April 28, it was the No. 3 film in America, beating DreamWorks Animation’s “Boss Baby,” Tom Hanks in “The Circle” and other Hollywood fare. It did so even though it opened on only 425 screens around the country,...