Born on August 21, 1928, in Sialkot, Pakistan, O. P. Ralhan is a producer, screenwriter, director, and actor who made several hit movies in the 1960s to 1980s. He began his vocation on the big screen by doing small roles in the 1950s. He mostly played comic characters in films. He often worked with well-known actor Rajendra Kumar as an executive, producer, and co-star, who also is his brother-in-law. In 1960, Ralhan acted as a friend of Rajendra Kumar in the romantic drama motion picture Pyar Ka Sagar. He dressed as a woman for a song sequence, which is his most memorable character as an actor. After acting as a supporting artist in many films from the 1950s to 1960s, he finally got finance to make his first movie named Gehra Daag in 1963 featuring Mala Sinha, and Rajendra Kumar in the lead and Mumtaz played her first adult character in the film.

The motion picture marked his successful entry in the Hindi cinema as director and producer. In 1966, he gave then performing artist Dharmendra the film titled Phool Aur Patthar, which became his first golden jubilee hit and made him a superstar. He executed and produced the movie, which went on to become the highest grosser of the year. It was Ralhan, who also gave a break to Zeenat Aman and Kabir Bedi with his movie Hulchul in 1971. He also gave work to then struggling artist Amitabh Bachchan in his motion picture titled Bandhe Haath in 1973 alongside Ajit and Mumtaz. In 1977, he made the film Paapi featuring Zeenat Aman, Sanjeev Kumar, and Sunil Dutt. Ralhan wedded Manorama, sister of on-screen character Rajendra Kumar.

He had two kids a son Munish Ricky Om Prakash Ralhan and a little girl Rupalli Pradeep Shah. His daughter’s son Armaan has taken his granddad’s last name Ralhan to proceed with the inheritance of his granddad in Bollywood. He is best recognized as the Director and furthermore its maker for movie Talash in1969 starring Rajendra Kumar and Sharmila Tagore as main characters. The film was, maybe still is, very pleasant to watch and had fantastic music by composer Sachin Dev Burman. It was the most expensive motion picture of that era. Ralhan was also a close friend to Sunil Dutt. He left the world on April 20, 1999, in Mumbai, Maharashtra after a long illness and later getting a cardiac arrest. His grandson Armaan Ralhan made his debut as the fiancé Aney in Hindi cinema with motion picture Befikre in 2016 alongside Vaani Kapoor and Ranveer Singh.