Mumbai, Apr 14 (PTI) Having known Shah Rukh Khan for over 25 years, Bollywood producer Vivek Vaswani feels if the superstar's upcoming "Fan" hits the right chord, it might become the biggest hit of his career.

Vaswani, who produced Shah Rukh's "Raju Ban Gaya Gentleman" and "Josh", hopes that the charm of the actor's earlier films is back with his drama-thriller.

"I hope the old Shah Rukh Khan is back (with Fan). I don't know on which holiday he went after 'Ra.One'. We want to see the old Shah Rukh of 'Raju Ban Gaya...', 'Darr'," Vaswani told PTI.

Directed by Maneesh Sharma, "Fan" features the 50-year-old actor in a dual role, that of a superstar and his lookalike fan.

Vaswani, who lived with the "Chennai Express" star when he was an aspiring actor in Mumbai, feels the movie can turn either way depending on how good the content is.

"See, if Shah Rukh pulls it off, then nothing like it. I have a friend who watches films first day first show and tells me a good analysis of how the film will do, business and the audience reaction wise. So, if people of his generation are disappointed with the film, then it won't work," he said.

"But, if they are not, then it will be the biggest hit of his career. It'll go either this way or that way. The trailer is good. Everyone is keenly awaiting the new Shah Rukh, including Shah Rukh himself," he added.

Even though he has produced films starring Shah Rukh and shares a good bond with the "Dilwale" actor, Vaswani has no intentions of directing a film with him.

"I don't have the financial stability to direct films. It is a completely different ball game today. I am very much happy helping my friends, acting as consultant for movies.

"I gave three back-to-back hits in the 90s and I am content with that. Till this date, people thank me for 'Raju Ban Gaya...' Even Shah Rukh. But, I never intend to make films."

Vaswani will be seen in a cameo role in filmmaker Vivek Agnihotri's next, "Buddha In A Traffic Jam".

"Fan" releases on Friday.