The film revolves around the titular con artist (Motilal) who manipulates an actress (Padmini) and a merchant (Kanhaiyalal) for his own benefits.

Since the city of Bombay loves theatre actress Malini of the Kala Mandir Company, he plots and concocts an elaborate scheme involving her and Seth Makhanlal, a ghee merchant.

He uses Malini, helps Makhanlal win the local elections, then has them involved in opening a bank by offering customers higher interest.

"[7] Padmini was chosen to reprise the role of Malini, originally played by Pushpavalli in Tamil,[8][9] and Mr. Sampat marked her first major appearance in a Hindi film.

[14] The film had no romantic duet, no bhajan, no rakhi song and no heartbreak track, all of which were considered "essential ingredients" in 1950s Indian cinema.

[15] Rati Batra of the magazine Thought wrote on 10 January 1953, "Motilal as Mr Sampat lives upto the character perfectly, and, though he gets all the laughs, he never borders on the clownish."

She also praised the performance of Padmini as Malini but criticised the photography, noting that the shots of the stage shows seen in the film suffered from "bad lighting".

He concluded that, despite a few minor objections, Mr. Sampat was a "shining example of film art amidst the morass of mediocrity that is the experience of the Indian cinegoer.

[23] Ghosh wrote in that book that the film's "post-mortem of corruption feels cool and contemporary even today" and that Motilal gave "the performance of a lifetime" as Sampat.