Country lad and Loveable Tramp Raj sets off to the big city in the hopes of making it rich. However, he is rejected and dejected because the city seems to only promote rich bigwigs and looks down on honest poor tramps like himself. He falls in love with Vidya who is struggling to make ends meet and care for her sick father. He is then slowly lured by corrupt business tycoon Seth Sonachand Dharmaanand and temptress Maya who teach him to deceive people to earn money. Raj gambles and wins by cheating though he tries to convince himself that he is only robbing rich people. When he realizes that the new venture he started on the advice of the Seth is a Ponzi scheme to wipe out the savings of the poor, he devises a plan to save both his reputation and put the corrupt Seth in jail. Until that point in time, he is tormented by a guilty conscience to lead a simple and honest life.
Not to be confused with 420 which is used to mean pot in Cannabis culture. In India, Section 420 of the penal code deals with con-artists. So, 420 is slang for a con-man, and 420ing is slang for conning someone.
TV Tropes include
- An Aesop - This being a Raj Kapoor film...
- Betty and Veronica - Maya as Veronica, Vidya as Betty though Maya is never shown as competition but as a degrading character
- Breakaway Pop Hit: Ichak Dana Beechak Dana became very popular in Israel; although nowadays people are only familiar with the ichak dana part, as its reached memetic status, and have no idea where its from. Try not to think about this too hard.
- Clearmy Name - Raj to escape the Seth's scheme
- Closerto Earth - Poor people are almost always better morally than rich people. Rich people are almost always pretentious bastards.
- Corrupt Corporate Executive - The Seth
- Country Mouse - Raj
- Ear Worm - Again, a feature of Shankar JaiKishan films. Cue Pyar Hua Iqrar Hua 
- Happy Rain - Cue Pyar Hua Iqrar Hua
- Meaningful Name - Vidya means knowledge. Maya means illusion. Sonachand means gold and silver.
- Theme Song - Mera Joota Hai Japani. See above lines.
- The Vamp - should be renamed Maya
- Those Two Actors - This being a Nargis and Raj Kapoor film.
- Visual Pun: When Raj first meets Seth, the latter angrily kicks him out of his car for conning him; Raj says, If Im a con man, a 420, then youre a... Seths car drives off before Raj can finish his sentence, revealing a licence plate with the number 840, that is, a double-420.
- Cool Teacher: Vidya