The party took place on Thursday night.
"These days, films don't last inside theatres beyond a week or two. And 'Rahasya' has gone into its sixth week in theatres. That's a great achievement," Gupta told IANS.
The film's lead actor Kay Kay Menon says the film's successful run "proves that real acting can prevail over so-called star power."
Tisca, who is known for her versatile performances, says "the film has sustained because of the audience's appreciation. What better compliment can an actor get?"
"Rahasya", a murder mystery about an 18-year-old girl who is killed in her own house, released on Jan 30.ALSO READ: 'Bambai Meri Jaan': Prime Video unveils a story of dreams, ambitions, and the insatiable quest for powerALSO READ: The Railway Men trailer: A tale of heroism & resilience ft. R. Madhavan, Babil, Kay Kay Menon, Divyenndu