Once upon a time in Bollywood, a handsome hero would croon and bash up a few goons to win over his coy but willing lady love. If the film worked, the director could live happily ever after.

But the staple heterosexual romance is no longer the only stuff that Bollywood dreams are made of, as filmmakers turn to subjects that would previously have been considered too serious or unthinkable for a conservative audience.

That is why there is much buzz about the industry's latest offering, "Dostana" (friendship), a film about two men who pretend to be a couple, in which homosexuality -- illegal in India -- is a running theme.

"I think the film does a lot for gays in a country where the word homosexual does not even exist for many people," said leading gay rights activist, Ashok Row Kavi

Homosexuality is punishable by a fine and a 10-year prison term in India, where a law prohibits "carnal intercourse against the order of nature," although convictions are unheard of.

A court in New Delhi is currently considering a suit brought by gay rights activists to decriminalise homosexuality, which is seen by many Indians as a "Western" import.

"Men come to us and say they now know that there is a word for their feelings, as the term homosexuality is a recent construct," Kavi told AFP.

In the film, there is no such confusion as Bollywood actors John Abraham and Abhishek Bachchan pose as a couple to win over a prospective landlady who is averse to renting out her apartment to single men because of her young niece.

Though the characters themselves are not homosexual, there are ample references to gay love -- a topic that had been largely shunned by Bollywood, except in one low-key but acclaimed film "My Brother Nikhil" three years ago.

""Dostana" gives a feel-good vibe without being gloomy or sending out wrong messages. It is very clearly gay, with Bachchan shown driving a pink limousine," said Kavi , who founded India's first gay magazine, Bombay Dost.

"Rarely will you get to see two popular desi (local) heroes indulge in such gay banter, even though it's make-believe," film critic Nikhat Kazmi wrote in The Times of India.

In one scene, the mother of one of the men finally comes around to accepting his "boyfriend" and wails: "Do I call you a daughter-in-law or son-in-law?"

"That is something new," activist Kavi said.

The two "gay" men ultimately end up chasing the landlady's young niece in Miami, where the film is set, giving the men plenty of scope to display their toned bodies in tiny trunks.

Produced by top filmmaker Karan Johar, "Dostana" is already on its way to becoming one of the biggest Bollywood hits this year, industry watchers said.

"It is doing very well among the younger, educated people in big cities," said Indu Mirani, entertainment editor of the tabloid Mumbai Mirror.

But Mirani cautioned against giving "Dostana" too much credit for championing the cause of gays and lesbians.

"It's too flippant, it won't change anything. Socioloigcal changes take years to happen," she said.

"The Indian audience is still not that evolved for Bollywood to try a film with gay characters in the lead."