The actor Rehman could have been an air force pilot in 1944 but turned to films instead. He first met Guru Dutt at Prabhat Studios that year and began a friendship that lasted until Dutt’s untimely death in 1964. They worked together on five films and Rehman continued to associate with Guru Dutt Productions even after his friend's death.
Rehman made his film debut in Hum Ek Hain (1946) alongside Dev Anand who was making his first on-screen appearance as well. Their friend Guru Dutt choreographed the songs. After key roles in Nargis (1946), Pyar Ki Jeet (1948), and Badi Bahen (1949), Rehman cemented his place as the friend of the hero and started gaining recognition for his performances. In his first Filmfare-nominated role in Phir Subha Hogi (1958), he appeared as Rehman, Ram Babu’s friend.
Loosely based on Fyodor Dostoevsky’s classic novel 'Crime And Punishment', the film starred Raj Kapoor as the guilt-ridden Ram Babu, who mistakenly kills a man while trying to help the woman he loves. When an innocent man does time for a crime he has committed, his conscience (and a persistent police officer) do not allow him to stay quiet.
Here, Rehman played a supportive friend, helping his friend whenever possible. That same year, he had a supporting role in 12 O’Clock, a murder mystery with co-stars Guru Dutt and Waheeda Rehman.
In Chaudhvin Ka Chand (1960), Dutt and Rehman took their friendship over to the big screen and played lifelong best mates, Aslam and Nawab Pyare Miyaan, who find themselves entangled in a difficult love triangle when they both fall in love with the same woman. As Pyare, Rehman sacrifices his affections for the beautiful Jameela (Waheeda Rehman).
But the image of the loyal, kind-hearted friend is not the one that lingers in most cinegoers’ minds. When most viewers conjure up Rehman’s name, they think of the characters he essayed in Pyaasa (1957), Chhoti Bahen (1959), Chhalia (1960) and, of course, Sahib Bibi Aur Ghulam (1962).
In all these films, Rehman is a man out for his own ambitions. As the publisher Mr Ghosh in Pyaasa, he is thinking of his bottom line when his wife Meena (Mala Sinha) brings him the poems of Vijay (Guru Dutt). As the younger brother Shekhar in Chhoti Bahen, he falls victim to the double vices of gambling and alcohol. After marrying a wealthy woman, Shekhar dissociates himself from his brother Rajendra (Balraj Sahni) and younger sister Meena (Nanda).
In Chhalia, a film set in the Partition days, he is Kewal, husband to Nutan’s Shanti. When Shanti is separated from him and bears a child in that period, he grows suspicious due to societal pressure and disowns her. It takes a good Samaritan, Chhalia (Raj Kapoor), to intervene and shows him his wife’s love and loyalty. Finally, in Sahib Bibi Aur Ghulam, as the degenerate Chhote Babu, he neglects his doting wife Chhoti Bahu (Meena Kumari) to the point that she becomes an alcoholic.
Rehman never ventured out to be a "villain" in his films. It was just his character’s choice to be entirely focused upon himself, while not caring a whit for anyone else. In Yeh Raaste Hain Pyar Ke (1963), he seduces a married woman and in Yash Chopra’s multi-starrer Waqt (1965), as Chinoy Seth, he manipulates brothers Raja (Raaj Kumar) and Vijay (Shashi Kapoor) into doing his bidding.
This kind of realistic villain was new at the time in Hindi cinema. On screen, he was selfish and immoral but not entirely black. Rehman’s portrayal of his characters were grey in the finest sense, especially in a Guru Dutt production like Pyaasa (1957), and therein lies his cinematic legacy.