Don was one of the wholesome entertainers. This was possibly Big B's first attempt at comedy. It was just that Amar Akbar Anthony was released earlier than Don because the latter almost got shelved after its producer, Nariman Irani (NI), died on the sets during the shooting. It is a pity that Mr NI never got to see the success achieved by his product. It did enough business to take care of the loan of 12 lakhs that had stressed him out and even kept his production house alive. NI was a photographer and cameraman by profession, who was under huge debt following the debacle of Zindagi zindagi, was pursuaded by the big B, Zeenat Aman and Chandra Barot to make another movie to settle the financial mess. Amitabh and Zeenat agreed to work for the film at nominal rates. Factually, Pran was paid 5 lakhs and Amitabh agreed for half of it. Salim-Javed's payment was the distribution rights of the film for the Indore and Bhopal territories.
The hit duo of Salim-Javed had approached Jeetendra, Dev Anand and Prakash Mehra with an untitled script based on 'House of secrets'. With no takers, the script was left collecting dust with Salim. When NI requested him for a script, he said- 'Humare paas ek breakfast script padi hai jo koi nahi le raha hai.' NI gleefully accepted - 'chalega'.
In Farhan Akhtar's version the 'Khaike paan banaraswala' song starts with the words:
Arre tumka ka bataai bhaiyya, hamraa haal kaa hai?
(chorus: arree bataai do, bataai do)
Nikle the halwa khaane, muh hi jal gaya hai!
Ironically, this is exactly what had happened to Amitabh because he was made to chew 40 paans to get the red-spew-effect. Anandji had suggested this, but he forgot to mention that for the red one need not apply chunaa (lime) to the paan. Amitabh suffered from burnt lips for days after the shoot. On the other hand, to grant authenticity to the song, Kishore Kumar ate paan and spat on a plastic sheet during the recording. The song was not part of the original screenplay and was added after the interval following Manoj Kumar's suggestion to bring down the pace a bit. The song, eventually, played a big hand in the popularity of the film. Another late addition to the screenplay was Pran's broken story which was a result of an accident he had met.
Inspite of the success, Hindi screen did not get any more films directed by Chandra Barot. In 1996 'Nariman Pictures' produced 'Shastra'. A remixed version of 'Don' was presented by Farhan Akhtar which scored over the original in the technical department, but, it could not make an impression as the version by late Mr. Nariman Irani.