Bollywood superstar Amitabh Bachchan's appeal to Indian audiences appears undiminished after he delivered early ratings success to Sony Entertainment Television (SET) in the relaunch this month of the quiz show Who Wants To Be A Millionaire, known in India as Kaun Banega Crorepati (KBC).

Bachchan, who turned 68 the same day KBC's fourth series began running on October 11, is reprising a role from a decade ago, only this time with a different channel. He was the inaugural host of KBC in 2000, when it catapulted SET's rival Star Plus (owned by News Corporation, which also owns The Australian) to the top of the ratings among Hindi general entertainment channels – the most lucrative part of India's crowded television firmament.

This time around, KBC's opening episode scored 6.2 television viewer rating points – a far cry from the double-digit ratings of 2000, but a huge success in an Indian television universe that has expanded to 500 channels over the last 10 years.

Man Jit Singh, CEO of Multi Screen Media, which runs SET and six other Indian television channels, told The Australian this week that he was delighted with KBC-4's ratings and it had established itself as "the unquestioned king of the non-fiction shows currently playing in India."

He said that when SET was conducting market research ahead of a relaunch, the "overwhelming response was that if KBC was coming back, it should have Mr Bachchan as the host."

Bachchan, known as the "Big B" of the film world, has been a fixture of the Indian entertainment scene for four decades, making his movie debut in 1969. He held the KBC role for two long runs between 2000 and 2006 before illness sidelined him. Star Plus opted to use his younger rival Shah Rukh Khan for KBC-3 in 2007, but the show ended after only four months. KBC was put on the shelf after that, before SET bought the rights in 2008 as part of its comeback plan.

In recent years SET has languished in fourth place among the Hindi general entertainment channels (GECs), behind Star Plus, newcomer Colors and another long-time rival, Subhash Chandra's Zee Entertainment.

Figures from the industry survey agency Television Audience Measurement (TAM) show that SET had just 11.7 per cent of the Hindi general entertainment audience before the relaunch of KBC, well behind Star Plus on 23.8 per cent, Colors on 21.3 per cent and Zee on 18.6 per cent.

Bachchan and KBC-4 have given SET a major boost since then in both viewers and sponsorship, giving credence to Singh's turnaround plan for MSM.

"There has been a terrific response from advertisers and the show is completely sold out," Singh said this week. "We started with eight sponsors that were signed on weeks before the show opened and our spot sales were completed the first week of the show."

Industry sources say that 10-second spots on KBC were sold for 250,000 to 300,000 rupees, or about A$5700 to A$6800 each.

With strong economic growth delivering more money into the hands of 1.2 billion Indian consumers this year, the number of TV households in India is expected to reach 132 million by 2012.

According to a recent study of the Indian media and entertainment industry by KPMG, advertising and subscription revenue for TV will grow to about A$18 billion by 2012. And while there is a growing push into more regional language offerings, Hindi GECs dominate the revenue stream, taking about 35 percent of all advertising spending.

According to Singh, MSM, which is the Indian arm of Sony Pictures Entertainment, has had a "tremendous year" after a subdued performance since the mid-2000s.

"Today we have two of the top five Hindi GECs in our network (SET and SAB) and three of the top 10 channels (SET, SAB and sports/movie channel MAX) in India. Our strategy and channel positioning is clear and the ratings have validated our approach," he said.

Still, Singh has his work cut out in the GEC arena to grow and hold his market share. Altogether, there are 12 general entertainment channels doing battle for an immense Hindi-speaking audience that is worth more than A$7 billion in advertising revenue.

Star Plus has held the top spot for a decade, although it has been pressed in recent months by the aggressive, disruptive programming of Colors, launched in July 2008 as a joint venture between U.S. entertainment major Viacom and the fast-growing Network 18 media group set up by former TV anchor Raghav Bahl.

In an interview in Mumbai in April last year, Singh told The Australian that SET aimed to get back the No. 1 or No. 2 entertainment spot it had occupied in the past.

"We may have lost our way a little. But we have a strategy to get back. You'll see us be edgier, more contemporary, with a skew to younger viewers," he said then.

Eighteen months down the track, Amitabh Bachchan and KBC -4 are an integral part of that strategy. Those younger viewers, it seems, respond well to the 'Big B' of Bollywood, judging from the steam of comments left on his Twitter page.

On his blog this week, Bachchan wrote that KBC is playing for the "celebration season of Diwali" (India's festival of lights). "An entire week dedicated to fun and joyous laughter; to be in the mood for lightness of spirit and joy."