Chennai Express released on August 9, and chugged its way into the Rs 100 crore club within its first weekend itself.
"When the film released and by Monday, Tuesday when we all got to know how is it doing and the reaction of the audiences, that made me feel that the years have spent in the industry have proved successful," the 47-year-old said here in an interview.
"The hard work that you do, the time that you spend and sometimes the good and the bad that you face, become worth it when you have a film like this," he added.
Chennai Express, which also stars Deepika Padukone, is said to have become the highest-grosser in Bollywood. Directed by Rohit Shetty, the entertainer has even crossed the Rs 200 crore mark at the box office.
While Shah Rukh is known more for his romantic image, with Chennai Express, he has been presented in a very different way - doing some over-the-top action stunts and loud comedy in his latest release.
He says being an actor, there is nothing such as a "comfort zone" for him.
"I am an actor and before films, I was in theatres. I do the film exactly how the director tells me to. Whichever role I am given, I give it my best and it is not like it is out of my comfort zone," Shah Rukh said.
"I am also a producer. And if a comfort zone worries me, then I might as well make my own films. But I like to do films the way a director wants me to and I feel happy. So, there is no such thing as a comfort zone for me," added the versatile actor.