CID was really Raj Khosla's breakthough film. Khosla had initially entered the Film Industry with hopes of making it as a playback singer. He however went on to become one of the great directors of Hindi Cinema. He assisted Guru Dutt through the making of Baazi (1951), Jaal (1952) and Baaz (1953) before getting a break with Jaal's producer and making Milap starring Dev Anand and Geeta Bali. The film however failed to create waves but fortunately for Khosla, mentor Guru Dutt was behind him and produced CID for him.

Following trends set by films like Sangram (1950) and Baazi, a spate of urban crime thrillers were made in Bollywood in the 1950s and 1960s. These films were influneced by the film noir movement of Hollywood. CID represents one of the most polished efforts in this direction. The suspense portions are extremely well handled and integrated seamlessly with other elements like romance and music to produce a high calibre fast paced thriller. In fact, CID remains one of the best crime thrillers made in Hindi Cinema highlighted by Khosla's stylish shot taking, extremely competent actor handling and innovative song picturisations, something passed down from Guru Dutt. VK Murthy's evocative camerawork beautifully recreates the noir world of Bombay - the dingy alleys, the wet roads, use of dark shadows, on location shooting whereever possible making Bombay very much a character of the story..

Dev Anand effortlessly plays his role of the CID Inspector though for once he is the man representing the law rather than a man living a live of crime on the streets of Bombay. By now a common fixture in the urban crime thrillers of the 1950s, he had also begun to acquire his starry accessories - the puff in the air, sing-song delivery and total nonchalance were becoming a part of every role he played. Shakila makes an ideal supporting heroine, one of her few big A-grade films and Johnny Walker is at his comic best. Mehmood makes the best of his small role. Stardom was still a way off for him yet. However they are all eclipsed by Waheeda Rehman who makes a stunning Hindi film debut in the film as a vamp! Born into a traditional Muslim family in Hyderabad, Andhra Pradesh, she was trained in Bharatnatyam. Her first film was the Telegu film Jaisimha (1955) followed by Rojulu Marayi (1955), which was a huge success. She was spotted by Guru Dutt in a song in the latter film and was brought to Bombay and cast in the film. She scores highly in the film particularly in the sequences where she tries to bribe Dev Anand or in the song Kahin Pe Nigahein Kahin Pe Nishana as she tries to seduce the villain and allow the hero to escape revealing her extraordinary facial mobility and dancer's grace. Khosla maintained he learnt the ropes of directing actors from Guru Dutt who taught him to focus on the eyes of the performance as it is the eyes that are the most expressive.

"Guru Dutt told me that eighty per cent of acting is done with the eyes of the actor, and twenty per cent the rest."

Another high point of the film are the songs. CID represents OP Nayyar at his peak - Each of the songs a raging hit be it Leke Pehla Pehla Pyaar, Aankhon hi Aankhon Mein Ishaara Ho Gaya, Ae Dil hai Mushkil (The Bombay song even if it is 'inspired' by My Darling Clementine!), Bhooj Mera Kya Naam re, Kahin pe Nigahein Kahin pe Nishaana and Jaata Kahaan Hai Deewane. The last is one of the best songs ever rendered by Geeta Dutt in her unique seductive style but unfortunately. though a big hit musically, the song does not find itself into the film. It is said the censors did not approve showing a CID officer being bewitched by a vamp! There was also objection to the use of the word Fi-Fi (Kuch Mere Dil Mein Fi-Fi, Kuch Tere Dil Mein Fi-Fi...) as being too suggestive! CID is also known for it song picturizations, something Khosla would always be famous for.

CID was a huge success at the box-office. Guru Dutt offered Khosla another film but this time Khosla declined telling Dutt,

"I am a small plant and I can't grow under a big tree."

Grow he did on his own becoming one of the most innovtaive directors of Hindi cinema effortlessly making all types of films be it crime thrillers (Kala Pani (1958)), musicals (Ek Musafir Ek Hasina (1962) - whose starting point was seven songs composed by OP Nayyar), suspense thrillers (Woh Kaun Thi (1964), Mera Saaya (1966), Anita (1967) - his mystery trilogy with actress Sadhana), 'social melodramas' (Do Badan (1966), Do Raaste (1969)) or dacoit dramas (Mera Gaon Mera Desh (1971) - which inspired Sholay (1975)).