Never heard of Rahul Roy? The Indian actor once had to regularly fight off admiring crowds that assailed him every time he appeared in public.

But times have changed: Now, while taking a break from his job at his family business, Roy, star of a 1990 Mumbai blockbuster about a struggling musician who falls in love with an orphan, can loiter anonymously on a street corner.

Unable to duplicate the show-stopping performance of his debut Aashiqui, Roy faded from the limelight after tasting fame, cast out from the celebrity cocktail parties and magazine covers he formerly graced.

In her debut documentary, Sunset Bollywood, Hong Kong filmmaker Komal Tolani dusts off the stories of Roy and several other cinematic one-hit-wonders as she explores what it means to make it big on the Hindi silver screen.

While escapades of Hollywood's rich and famous are widely exposed in the international media, Tolani's film sheds light on the culture of fame in India.

Sunset Bollywood

traces the careers of three actors - Roy and former stars Bhagyashree and Kumar Gaurav. The film shows fresh young Bollywood celebrities intoxicated by fame. All three got their first break unexpectedly: Roy in Aashiqui (1990), Bhagyashree in Maine Pyar Kiya (1990), and Gaurav in Love Story (1981).

Each catapaulted from anonymity to tabloid fame and the poshest Mumbai parties.

But, for reasons ranging from bad luck to choosing to start a family, each failed to produce a repeat hit.

Sunset Bollywood is no fiction: It gives a glimpse of the vast industry generated by the Bollywood cinematic machine.

Hoping for stardom, each year thousands of aspiring actors and actresses, singers, dancers, models and beauty contestants flock to Mumbai, formerly Bombay, hence the "B'' in Bollywood .

In a country of 1.1 billion people, many of whom live in poverty, the movie screen can be a ticket to riches and instant national recognition. In southern India, Bollywood stars are sometimes even worshipped at small house shrines.

"To be a star in India is like being God. There are a billion people worshipping you,'' says Tolani, who spent her childhood pining for Rahul Roy

While shooting her film in Mumbai with her own Bindaas Productions company, the British-educated, Hong Kong-based filmmaker spent six months attending parties, haunting production sets, and hobnobbing with Bollywood casts.

"I was on the outside looking in at the madness that is Bollywood,'' she says.

The sheer size of the Indian film industry amplifies the fame and adulation accorded its stars.

Releasing almost 800 Hindi films per year, India produces more movies than any other country in the world. Televised Bollywood movies garner more than 11 million viewers each day in India, South East Asia, and across to Africa, according to Turner Classic Movies.

Most Hindi films are musicals featuring song and dance routines and spectacular sets, all amounting to an elaborate fantasy world into which the mass audience can escape briefly.

Angry parents, bedevilled lovers, siblings separated at birth, corrupt politicians: These are the stock characters that have historically won mass appeal. As an actor or actress, once you win over the audience on the magical screen, offstage you are superhuman.

Sunset Bollywood shows Rahul Roy, hypnotized by fame, making a string of bad career decisions. Following Aashiqui, his subsequent projects ranged from an Indian remake of the American classic Ghost (complete with a muddy love-making scene over a pottery wheel) to Junoon in which he turns into a werewolf. In that clunker's most awkward moment, the camera zooms in on fangs shooting out from Roy's upper gums.

Like Roy, Bhagyashree's and Gaurav's attempts to salvage their careers also resulted in embarrassingly bad productions.

Foundering in India but still hungry for fame, Rahul Roy goes to seek his fortune in Hollywood.

"I can probably get a spot on Beverly Hills 90210,'' he says but fails to capture a role or the recognition to which he feels entitled. Returning to Mumbai, he drinks his way through second-class cocktail parties before finally facing up to his depression.

According to Mumbai film critic Indi Murani, editor of Box Office magazine, Tolani's portrayal of Bollywood's capricious film industry is true to life.

In a world where directors compete to hire the most popular stars, not always the best actors and actresses, just one bad movie can mar an actor's chances of staying in the limelight.

"We take our actors to such great heights. The higher you go, the easier it is to fall. We expect our actors to be gods. We don't want them to have human frailties,'' Murani says.

Tolani adds: "It's this secret that everyone in the entertainment world has. You're doing really well but you have to ask yourself: `How long is the high going to stay? It could just go.'''

"Stardom is the same anywhere. Falling from grace is equally as hard in any profession. It's just in Bollywood, everyone knows about it,'' says Murani.

Today Rahul Roy is still at it. In his free time, he and a small non-Bollywood production house are on their fourth year of an Indian remake of the Lion King. Roy will play Simba.

"I'll get back there some day. It may take 20 years, but I'll be there,'' he says of Bollywood.