MUMBAI, India — Aamir Khan spent more than two decades as one of India’s most admired movie stars, appearing in a string of socially conscious but mainstream films.

Now he has gained even more fame as the host of a popular weekly television show that is calling attention to some of the country’s longstanding social problems.

Mr. Khan’s show, “Satyamev Jayate,” or “Truth Alone Prevails,” is taped in front of a live audience, and is something more than a talk show but short of “60 Minutes.” Mixing Oprah-style interviews on a couch with short reports from the field, it tries to shine a spotlight on festering issues like dowries, domestic violence and the indignities of the caste system.

In just three months, the Sunday morning show has become a national phenomenon, distributed in seven languages and drawing a cumulative audience of nearly 500 million, according to Star India, the network that broadcasts it.